Message Broker and WTX integration :Running multiple instances of maps with message flow

Running multiple instances of maps

              There are some restrictions you should note when you use a precompiled map concurrently in more than one broker message flow, or when you use a map in a broker message flow with multiple threads of execution. You allocate multiple threads by setting the message flow's Additional Instances property in the broker archive editor in the WebSphere Message Broker Toolkit.

- If you have used Map Settings to switch map audit on, and are using an AuditLocation of "File," then you must set the audit FileName to "Unique." Failure to do so causes the map to fail with error code 53, and to throw an exception.

- If you have used Map Settings to specify a WorkSpace of "File," which is the default, then you must set the WorkFilePrefix to "Unique." Failure to do so causes the map to fail with error code 36, and to throw an exception.

- If you have used Map Settings to switch map trace on, then only the first message flow thread that runs traces to the designated file. Other message flows and other threads fail to trace. Note that the map does not fail, and it does not throw an exception. It is not possible for you to specify "Unique" for the trace FileName.

- If you have used Edit Input Card or Edit Output Card to switch backup on for a card, then you must set the backup FileName to "Unique." Note that the map does not fail, and it does not throw an exception.

There are additional restrictions you should note when you use a map in a broker message flow with multiple threads of execution.

- Enable map caching by selecting the Map cache property in the Basic tab under Properties for the WTX Map node in the WebSphere Message Broker Toolkit. Failure to do so might cause the map to fail.

Padding Difference in Input and Output Side

If padding is used for particular item in WTX then how it works ?

   Consider the structure is having fixed lenght of 10 with padded 0.

     1) If type tree is used in input side of wtx.If data is less then 10 chars then remainig chars     should be present in fixed lenght with padded 0.

     Ex. input data is 12345 with 5 chars only then 5 ''0'' should be present for validating data proper in this case.The data to satisfy above condition is without invalid error will be as :

  0000012345.

Note : 

         If the input element is dragged on any output element then you can find only 12345 as if input element is padded by char [in this case 0 ] then resulting element at output side will be without padding.

2) If type tree is used in output side of wtx.If data is less then 10 chars then remainig chars will be added automatically in fixed length with padded 0.

     Ex. Output data is "12345'' is hadcoded value then 5 ''0'' will be added automatically  in this case.The data to satisfy above condition is with invalid error will be as :

  0000012345

Mercator WTX 8.1 interview questions

• EDI
  Is the X12 file positional delimited or literal delimited?
  Both positional and literal delimited… ISA record positional delimited (total 106 characters) and remaining * or / etc delimited
  
  What is EDI? Electronic Date Interchange. EDI is simply sending and receiving of information using computer technology. Its efficiency has made it a condition of doing business in dozens of industries (retail, grocery etc.,) .Any standard business document that one company would exchange with another (like PO ,invoice ,Health Care claim) can be exchanged via EDI between the two parties or trading partners, as long as both have made the preparations. EDI is transmitted in a structured format, based on the use of message standards, which ensures that all participants use a common language.
  What are the uses of EDI? 1) Manage Huge volumes of transactions
  2) Less Operating Cost
  3) Eliminates delays
  4) Eliminates data entry errors
  5) Bridges the information gap that exists between companies using different computer systems.
  6) Elimination of paper documents
  7) Greater accuracy of information
  8) Better tracking
  9) Speed. Because information is moved faster and with greater accuracy, time spent communicating with the suppliers decreased.
  
  What are the various formats/flavors available in EDI? ANSI-X12 à American National Standards Institute, EDIFACT à EDI For Administration, Commerce and Transport ,
  XML à Extended Markup Language, CSV à Comma Separated Value
  
  What is EAI? EAI is an industry term used to describe the infrastructure needed to facilitate disparate applications communicating together. With EAI all the applications are communicating via a central system, or middleware. No specialized programs at either the source or destination location perform this data translation from one format to another. It is the responsibility of the EAI system to provide a service to change the data formats between the two applications.
  
  What is an inbound file?
  Inbound file is an EDI file received from a trading partner and its data gets parsed or mapped to an existing system (Legacy system)
  What is VAN? Communication between trading partners is usually handled by a carrier. The carrier, also known as a third-party network or Value Added Network (VAN), acts like a postal service between trading partners, who are using standard communication protocols.
  What is an EDI Translator? For the bookstore system to have a consistent EDI interface, an EDI translator is essential. The EDI translator normalizes the EDI documents going to and from the bookstore system to the trading partners. EDI translators are available from a number of independent companies who not only provide the translator software, but also provided updated dictionaries, as new revisions to the standards become available.
  What is an outbound file? Outbound file is an EDI file generated data out of an existing (Legacy) system sent to a trading partner.
  
  Mercator – general
  What is the main strength of Mercator? Partitioning is the main strength of Mercator.
  
  What are mrc and mrn files? Where will you use them?
  Mrc - This is the filename extension for a resource configuration file. A resource configuration file contains specifications for an engine such as the active virtual server(s) and its associated .mrn file. Mrn - This is the filename extension for a resource name file. A resource name file contains a named set of virtual servers and a named set of resources. Each named resource specifies a value for that resource for each virtual server.
  
  What is resource register?
  The Resource Registry is an application that is used to define name aliases for source and target resources that are specified in map cards.
  
  What is “ini” file?
  The dstx.ini file is the configuration file for Ascential DataStage™ TX and contains specific settings for the Event Server. The file is created in the root directory during the installation process. You can use a text editor to edit option values as needed. The dstx.ini file contains default initialization settings for the Event Server under the following headings:
  ¨ Launcher
  ¨ Resource Manager
  ¨ Connections Manager
  
  What is Process Control File?
  Process Control File has the information which is supplied to the Command Server that controls the processing of maps. The Integration Flow Designer can generate command files that control Command Server processing and event server files that control Event Server processing.
  Type Designer
  What is $=$ in component rule?
  $=$ è When the particular component is present the validation should proceed without throwing any warnings/errors.
  
  How can you incorporate validation in a type tree?
  By using component rule validation can be incorporated in a type tree.
  What is component Rule? Is it advisable to use Component Rule?
  A component Rule is an expression about one or more components. It indicates what must be true for that component to be valid. For given data, it evaluates to either TRUE or FALSE.A component rule is similar to a test, it is invalid. A component rule cannot be greater than 32K. No it is not advisable to use Component rule.
  
  What is release Character?
  A release character is a one-byte character in the data that indicates that the character(s) following it should be interpreted as data, not as a syntax object. The release character is not treated as data, but the data that follows it is treated as actual data. Release characters apply to character data only, not binary data.
  If a release character is defined for a type, a release character is inserted for each occurrence of a syntax object in the data of any item contained in that type.
  
  The following options are available for the Release property.
  
  Value Description
  None Release characters are not enabled.
  Literal The release character is a constant value defined by the Release > Value property. Expand the Release property to define the literal release value.
  Variable The release character is a variable value defined by the Release > Default, Item and Find properties. Expand the Release property to define the variable release values.
  
  What is sized attribute? The sized attribute specifies that the value of the given component represents the size of the following component. The sized attribute is used on a component whose value specifies the size (in bytes) of the component immediately following it. The sized attribute can be used on more than one component of a group.
  
  Size
  For example, you may have a variable length component with a number immediately preceding it that indicates the length of the component:
  10Washington -- The 10 indicates the size of the following component.
  
  Some important points about using the sized attribute are:
  
  ¨ the component with the sized attribute must be defined as an unsigned integer.
  
  ¨ If a binary byte stream item does not have a fixed size, the component preceding it must specify its size and the sized attribute must be used on that component.
  
  The size of a component is the number of bytes from the beginning of that component, up to and including the end of the component. If a component has a series range [such as (1:3)], the size includes all of the members in the series of that component. If a delimiter separates each member of that series, the delimiters must be included in the size. Also, if release characters appear in the component, they must be included in the size.
  The size does not include delimiters that separate one component type from the next.
  
  What is Restart attribute? The restart attribute specifies an error recovery point. In order to map invalid data of a particular object, errors during validation are ignored by assigning the restart attribute. Then you can map the invalid data using any or all of the error functions REJECT, ISERROR, and CONTAINSERRORS. To continue processing your input data when a data object of a component is invalid, assign the restart attribute to that component.
  Note Do not put the restart attribute on a required component. There must be a sufficient number of valid instances to cover all the required components. If you have a required component, that is not valid, the restart attribute will not validate the data.
  
  What is identifier? When creating type trees and defining components of a group, the identifier attribute can be assigned to one component to identify a collection of components that is used during data validation to determine whether a data object exists. The identifier attribute can be used on a component of a group. The identifier indicates the components that can be used to identify the type to which a data object belongs. All the components, from the first, up to and including the component with the identifier attribute, are used for type identification.
  When this data is validated, it knows that, when it reaches the identifier, it has found a specific group. That group, therefore, is known to exist, even if part of the group following the identifier is missing.
  
  What is a fixed and delimited property?
  The size of the element will be fixed in fixed. A fixed group can have only fixed components. If the size of the field is 10 and actual size of element is 5, 5 spaces will be padded to the output. In fixed group components are identified by their position. In delimited group, components are identified by delimiter.
  
  Restrictions in type tree? Exclude and include
  
  What are the different types of analysis? Logical and structural analysis.
  Logical Analysis
  Logical analysis addresses the integrity of the relationships that you define. Logical analysis detects, for example, undefined components, components that are not distinguishable from one another, item restrictions that do not match the properties of that item, and circular type definitions. The analyzer also checks delimiter relationships, and logic errors contained in component rules.
  Structural Analysis
  Structural analysis addresses the integrity of the underlying database. Structural analysis may be able to detect and possibly correct defects caused by system environment failures. Typically, you should not encounter structural analysis error.
  
  
  What are the group subclasses?
  Group types have a subclass of Sequence, Choice, or Unordered.
  Sequence
  A partially-ordered or sequenced group of data objects. Each component of a sequence group is validated sequentially.
  
  Choice
  Choice groups provide the ability to define a selection from a set of components like a multiple-choice question on a test. Choice groups are similar to partitioned groups. A choice group is validated as only one of its components. Validation of a choice group is attempted in the order of the components until a single component is validated. If the Choice group has an initiator, the initiator is validated first.
  
  Unordered An unordered group has one or more components. Unordered groups can only have IMPLICIT format property, with the same syntax options as sequence.
  
  What is partitioned property?
  If the data of a type can be divided into mutually exclusive subtypes, it can be partitioned.
  
  What is explicit and implicit?
  A Sequence group has either an Explicit or Implicit format. For example, if each component of a fixed group has a fixed size, the component is distinguished from the next component by its position in the data. Or, a group may have delimiters that appear for missing components. In these cases, the format is apparent; the group has an explicit format.
  If a group does not have an explicit format, it has an implicit format. An implicit format relies on the properties of the component types. In this example, the components make some pattern in the data and it is possible to distinguish between them, but the format is not fixed and if delimiters separate components, they do not appear for missing components.
  When deciding what format a group has, it may help to ask first whether it is clear where one component ends and another begins. Generally, a group has an explicit format if the position of each component in the data stream is always the same or if a delimiter always marks the place for each component.
  
  What is partitioning?
  Partitioning is a method of subdividing objects into mutually exclusive subtypes.
  Map Designer
  For a functional map A and B are parameters. A occurs 2 times and B occurs 3 times. How many times the functional map executes?
  2 Times...if particular occurrence of a parameter to a functional map is null the functional map will not execute that time
  
  What is LOOKUP function? The LOOKUP function sequentially searches a series, returning the first member of the series that meets a specified condition.
  
  Syntax
  LOOKUP (series-object-expression, single-condition-expression)
  
  Meaning
  LOOKUP (series_to_search, condition_to_evaluate)
  
  Returns
  This function returns a single-object. Returns the first member of series_to_search for which condition_to_evaluate evaluates to TRUE. Returns NONE, if no member of series_to_search meets the condition specified by condition_to_evaluate.
  
  Uses
  Use LOOKUP to find an occurrence of an object that meets a certain condition. LOOKUP performs a sequential search over series_to_search. Use LOOKUP if series_to_search is not ordered.
  
  What is EXTRACT function? The EXTRACT function returns each member of a series for which a specified condition is true.
  
  Syntax
  EXTRACT (series-object-expression, single-condition-expression)
  
  Meaning
  EXTRACT (series_to_search, condition_to_evaluate)
  
  Returns
  This function returns a series-object. The result is each member of series_to_search for which the condition specified by condition_to_evaluate evaluates to TRUE. EXTRACT returns NONE, if no member of series_to_search has a corresponding condition_to_evaluate that evaluates to TRUE.
  
  Uses
  Use EXTRACT whenever you need only particular members of a series returned—those that meet a certain condition.
  
  Note The EXTRACT function can only be used in a map rule. It cannot be used in a component rule.
  
  
  What is RUN function? The RUN function allows you to execute another compiled map from a component or map rule.
  
  Syntax
  RUN (single-text-expression [ , single-text-expression ] )
  
  Meaning
  RUN (map_to_run [ , command_option_list ] )
  
  The first argument, map_to_run, is an expression identifying the name of the compiled map (.mmc) to be run.Command_option_list is used to specify execution commands applicable to the map to be run. Command_option_list is a text item containing a series of execution commands separated by a space.
  Any execution command can be used as part of the command_option_list. For example, you can send another map data by using the echo command option (-IEx). See the Execution Commands Reference Guide for a list of command options.
  
  Note The command_option_list is optional.
  
  Returns
  This function returns a single-text-item. The result of the RUN function depends on the command options in command_option_list:
  
  § If you use the echo command option for an output card, the data from that card will be passed back as a text-item to the object in the map from which it was run.
  
  § If you use the echo command option for more than one output card, the data from all echoed cards will be concatenated together and passed back as a text-item to the object in the map from which it was run.
  
  § If you do not use the echo option, the return code indicating the status of the map that was run will be passed back to the object in the map from which it was run.
  Please refer to the attached document to know about the various options
  
  What is CLONE function? The CLONE function creates a specified number of copies of some object.
  
  Syntax
  CLONE (single-object-name, single-integer-expression)
  
  Meaning
  CLONE (object_to_copy, number_of_copies)
  
  Returns
  This function returns a series-object. The CLONE function returns a series of the object specified by object_to_copy. The output series consists of as many copies of the object as specified by number_of_copies. The value of each member of the resulting output series is the same as object_to_copy.
  Uses
  The CLONE function is useful when the number of output objects to be built depends on a data value, rather than the number of objects that exist in the data.
  
  What is CHOOSE function? The CHOOSE function returns the object within a series whose position in the series corresponds to a specified number.
  
  Syntax
  CHOOSE (series-object-name, single-integer-expression)
  Meaning
  CHOOSE (from_these_objects, pick_the_nth_one)
  Returns
  This function returns a single-object. Produces a single-object whose index is within the from_these_objects series matches the number specified by pick_the_nth_one. If that member of the series does not exist, CHOOSE returns NONE.
  Uses
  Use CHOOSE when you need to use a variable value to specify the index for a particular object from a series.
  
  What is COUNT?
  The COUNT function returns an integer representing the number of valid input objects in a series.
  Syntax
  COUNT (series-object-expression)
  Meaning
  COUNT (valid_objects_to_count)
  Returns
  This function returns a single-integer.The result is the number of valid_objects_to_count. If the input argument evaluates to NONE, COUNT returns 0.
  
  Note COUNT does not count existing NONEs unless its group was defined as an explicit format with a Track setting of Places.
  
  Uses
  Use COUNT when you need to count a series of input or output objects.
  
  What is INDEX function? The INDEX function returns an integer that represents the index of an object relative to its nearest contained object, counting only valid objects.
  Syntax
  INDEX (single-object-name)
  Meaning
  INDEX (object_for_which_to_get_index)
  Returns
  This function returns a single-integer. The result is the index of object_for_which_to_get_index.
  § If object_for_which_to_get_index is an input, this will be the index within all valid objects.
  
  § If object_for_which_to_get_index is an output, this will be the index within all objects (valid and invalid).
  
  Returns 0 if the input argument is NONE.
  
  Note The difference between INDEXABS and INDEX is that INDEXABS counts both valid and invalid instances, whereas INDEX counts only valid instances.
  
  Uses
  Use INDEX when you need to select or test particular objects based on their occurrence, as in the example above. Or, use index to add a sequence number to output objects.
  
  Note INDEX cannot be used in a component rule.
  
  What is the difference between COUNT () and COUNTABS ()?
  The COUNTABS function returns an integer representing the number of input objects in a series. Unlike COUNT, COUNTABS includes both valid and invalid objects in a series.
  
  What is PUT / GET function? The PUT function passes data to a target adapter. The GET function returns data from a specified resource adapter.
  
  What is a SEARCHDOWN function? The SEARCHDOWN function performs a binary search on a series sorted in ASCII descending order, returning a related object that corresponds to the item found.
  
  Syntax
  SEARCHDOWN (series-object-expression, series-item-object-expression, single-item-expression)
  
  Meaning
  SEARCHDOWN (corresponding_object_to_return, descending_items_to_search, item_to_match)
  
  Returns
  This function returns a single-object. Performs a binary search on the item series of descending_items_to_search. The descending_items_to_search must be sorted in ASCII descending order. The value to search for is specified as the item_to_match. The object returned (corresponding_object_to_return) must be related to descending_items_to_search by a common object name.
  If no match is found, SEARCHDOWN returns NONE.
  
  Uses
  Use SEARCHDOWN when data is sorted in ASCII descending order and you need to look up data within the sorted data.
  
  What is the difference between PACKAGE and TEXT function? PACKAGE when you need to convert an object to a text item that includes its initiator, terminator and any delimiters it contains. PACKAGE differs from TEXT in that it includes the initiator and terminator of the input object.
  
  What is the difference between LOOKUP and EXTRACT function? LOOKUP differs from EXTRACT in that LOOKUP returns the first member of series_to_search that meets the condition_to_evaluate, while EXTRACT returns all members (one at a time) of series_to_search that meet the condition_to_evaluate.
  
  How to find difference between to dates (dynamic values)? Using the DATETONUMBER () function. This function returns an integer that results from counting the number of days since December 31,1864 to the specified date.
  Different fetching modes of a map. How they differ? Burst and integral mode BURST MODE
  Burst mode allows data to be returned from an input or passed to an output in pieces (or bursts) rather than in a single large buffer of data. This is valuable if you are dealing with large amounts of data and it would not be feasible to pass all of the data in one retrieval due to memory limitations.
  When a map executes in burst mode, it processes all of the inputs, then the outputs, then revisits the inputs to determine whether they have any more data. This processing continues until all inputs in burst mode have exhausted their data.
  
  Within a map, some input cards may be in burst mode while others are in integral mode, which means that they are executed only once. To specify a database card to run in burst mode, change the SourceRule > FetchAs setting to Burst and specify the FetchUnit setting. The FetchUnit setting is the maximum number of rows that will be retrieved per fetch. The default is S which indicates that all of the rows are retrieved by the SELECT statement.
  
  Note If the SourceRule > FetchAs setting for an input card is set to Burst, its Transaction > Scope setting will always be Map.
  INTEGRAL MODE
  
  When messaging adapters are specified as the source of the data for an input card using integral mode (SourceRule > FetchAs = Integral), the adapter retrieves up to the number of messages specified with the Quantity adapter command (-QTY) in a single burst.
  
  Different error messages that a map will display? 1) One or more inputs invalid
  2) Input valid but unknown data found
  3) One or more outputs invalid
  4) Source not available
  5) Input type contains error
  6) Open audit failure
  7) Fail function aborted map
  
  How to capture invalid records? Using functions like REJECT,CONTAINSERROR, ISERROR
  
  How will you relate Partitioning and Choice?
  The components of a choice group are similar to the partitions of a partitioned type. However, a Choice group can have both items and groups as components. A partitioned Sequence group can only have group subtypes.
  
  Which one is efficient and optimized - !create or sink? , Justify your answer.
  !create is efficient when compared with sink
  
  !create – Regardless of whether or not data content is produced, output data is not to be sent to its target. This option is available for temporary data storage as a map runs.
  Sink – This adapter is used as a temporary data destination for an output map card which then discards the mapped data. This capability is useful when a temporary destination is needed to accept output data as part of the map execution without writing the output to a stationary destination.
  
  What is REJECT ()?
  The REJECT function returns the content of an object in error as a text item.
  Syntax
  REJECT (series-object-expression)
  Meaning
  REJECT (series_to_look_for_bad_objects)
  Returns
  This function returns a series-text-item. Evaluates to a series of text items consisting of all the input series members in error.
  Uses
  Used in conjunction with the restart attribute. For information about the restart attribute, see the Type Designer Reference Guide and the Map Designer Reference Guide. The REJECT function can be used only in a map rule. It cannot be used in a component rule.
  
  What is validation map? Validation Map is the map with which the input is validated against type definition.
  How to check map execution time?
  What is BUILD command?
  The BUILD command on the map menu is used to build the executable map for the selected map. The Build command analyzes the logical interfaces within map rules. The BUILD command generates the compiles map file with .mmc extension. Analysis includes checking for missing rules, invalid rules, invalid card definitions, verifying map references, and verifying the arguments of functions. Analysis also looks for circular map references - maps that reference one another.
  When a map is built, the map and all of the functional maps that are referenced within that map are analyzed. An executable map has a data source or target specified for each of its cards. Executable maps are built. Functional maps are not built.
  
  Note Data sources and targets specified for an executable map are defaults built into the compiled map file.
  
  What is functional map?
  A functional map is like a sub-routine; it maps a portion of data at a time. A functional is a map that is used like a function. It takes one or more input objects and generates one output object. For example, you might have a functional map that maps one Message to one row in a database table. Or you might have a functional map that maps one Header and one Detail to one ItemRecord.
  
  Note The results of the functional map are sent directly to the output card. They are not passed back to the calling rule.
  
  When to use a functional map?
  The use of functional maps is very common. Almost every executable map created will use at least one functional map. To map a group in the input to a different group in the output, use a functional map. For example, use a functional map to map an input row to an output row when the rows are defined differently. Or, use a functional map to map from a file containing many input rows, to generate a file of many output rows with one output row per input row. The first output row would correspond to the first input row, the second output row corresponds to the second input row, and so on.
  A map defines how to generate the output data. One important factor to consider in determining when to use a functional map is the presence of an output component with a range of more than one. For example, ranges of (s) or (1:10). The number of this output object to be created is based on the number of some input object. Another important factor in determining when to use a functional map is when you want to transform the data - mapping from one or more types to a different type. In the preceding example of the functional map that maps one Message to one row in a database table, the input row and the output row are two different types.
  
  Note Use a functional map when the number of a certain output group that you want to create is based on the occurrences of some input or output data - and the types are different types.
  
  What are the adapters have you come across? Database, File, Sink, MQseries, JMS.
  What is the difference between DBQUERY and DBLOOKUP function?
  character will be present at the end of output in DBQUERY and DBLOOKUP will not have.
  
  On performance basis which is best component Rule/Map rule? Map rule will be an optimized option
  
  Why ISError function is used in conjunction with restart function? Can ISError be used alone?
  
  Explain the use of Ellipses?
  Use of ellipses option causes the lengthy object names to display the shortest possible object name. Rather than having the entire a name appear, unique portions of the names are replaced with a period (.) that is used as an abbreviation of ellipses (…)
  
  Ex: Complete Object Name : company field: record: Input.
  Shortened Name : company field:.: Input
  
  Explain f (A, B) having 3 occurrences of A and 2 occurrences of B. A and B are independent. How many times this functional map does is called?
  6 times will be called (3C2-Combination of 3 and 2)
  
  Explain f (A, B) having 3 occurrences of A and 2 occurrences of B. A and B are dependent. How many times this functional map does is called? 2 times map will be called (A,B) (A,B)(A)
  
  3 A’s, 2B’s present in a single file segregate all A’s to one file and all Bs to another? File A => f(A) file => f(B)
  
  1000 A’s in one file separate each A to different files with different names? PUT(“FILE”, Name + (INDEX),PACAKGE(input item))
  
  RUN Function commands used in one function? -IF – Files(specify location) -IE direct data(override) -ECHOIN – package data path from calling map (make a copy) -HANDLEIN – (direct data) -OF -Summary –TS -Audit - AU
  -Output Sink –OASink
  
  What are the different Adapters?
  PFA the document to have an idea about the list of adapters
  
  What is organizer Window?
  The Organizer window contains information about the selected map. The information includes unresolved rules, remarks, audit settings, the trace file, the audit log, and build errors.
  The Organizer window has six tabs:
  
  ¨ Unresolved Rules
  ¨ Remarks
  ¨ Data Audit Settings
  ¨ Trace
  ¨ Audit Log
  ¨ Build Results
  
  Note If you select the Unique filename option for the audit log (Map Audit > Audit Location > Filename), the audit log will not be viewable from the Organizer window.
  
  Each tab on the Organizer window can be floated as a separate window. The font of each Organizer tab can be customized.
  
  What is EXIT function?
  The EXIT function allows you to interface with a function in an external library or application. Depending on the execution platform, there are two different methods for the EXIT function.
  
  Syntax
  EXIT (single-text-expression, single-text-expression, single-text-expression)
  
  Meaning 1 – Library Method
  
  Returns
  This function returns a single-text-item. Set lpep->nReturn equal to 0 if the function is to succeed or set it equal to 1 to fail. For detailed information on the requirements of the library function that is executed by the EXIT
  
  
  Meaning 2 – Program Method
  
  EXIT (program name, command_line_arg1, command_line_arg2)
  
  At execution time, the program specified by program name executes and passes the concatenation of command_line_arg1 + " " + command_line_arg2 as a text string.Whatever is returned by program name to the standard output device is returned as text.
  
  Returns
  This function returns a single-text-item. Returns a text string from the function or application that is executed. If the EXIT function is not available for a particular platform, EXIT returns NONE.
  
  Uses
  Use EXIT when you need information from an existing function in a library or a program, or when you need to use a general function that is not available.
  
  What is FAIL function? The FAIL function returns NONE, aborts the map and returns its argument as the map completion error message.
  
  Syntax
  FAIL (single-text-expression)
  
  Meaning
  FAIL (message_to_return)
  
  Returns
  This function returns NONE. Returns NONE to the output to which the function is assigned, aborts the map and returns message_to_return as the map completion error message included in the execution audit. The map return code will be "30", indicating that the map failed through the FAIL function.
  Uses
  Use the FAIL function to abort the map based on map or application specific logic.
  
  What is Trace File?
  The trace file is a debugging aid used to diagnose invalid data or incorrect type definitions. A map can be configured to create a trace file that can be viewed.
  The trace file is a text file that records map execution progress. Input data, output data, or both input and output data may be included in a trace file. Map settings and adapter commands are used to enable tracing.
  When input data is traced, the trace file provides a step-by-step account of the data objects found, why the data is found to be invalid, sizes and counts of data objects and their position in the data stream.
  
  A trace file of input messages contains a message for each input data object. Each input data object message describes the:
  
  ¨ level of the object in the card
  ¨ offset of the data object in the data stream
  ¨ length of the data object
  ¨ component number of the data object
  ¨ index of the component
  ¨ a portion of the actual data
  ¨ name of the type it presumably belongs to
  
  A trace file of output messages specifies which objects are built and which output objects evaluate to NONE.
  
  Note Because performance can be impacted, it is best to use the trace option only during debugging.
  
  30 maps are there in a System. How to find how many executed completely? By looking into event server log
  
  What is Pseudo Maps?
  Pseudo maps reference executable maps that have not yet been implemented. Pseudo maps are represented by PINK icon.
  
  How to convert pseudo maps to executable map?
  Pseudo maps are the only components in the Integration Flow Designer (IFD) that allow you to create source maps and add input/output cards.
  
  To create a source map from a pseudo map
  
  1. Right-click the pseudo map icon and select Create Source Map from the context menu.
  
  The Create Source Map dialog appears.
  
  If the map source file exists, click Browse to display the current list of executable maps in this map source file. If the specified map source file does not exist, or if no map source file is specified, an error message is displayed.
  You can sort the cards by number or by name. A card is undefined if any of the following are not specified:
  
  ¨ type tree
  ¨ type name
  ¨ source or target
  
  2. Click the Edit button to provide the missing information.
  The Edit Input Card dialog or Edit Output Card dialog appears, depending on the card currently selected.After all the missing information is supplied for a card, ok is displayed next to the card name. The Create button becomes active when all cards are defined and when the executable map name and map source file are defined and there is at least one output card.
  
  3. Click Create
  A map source file is created or the executable map is added to an existing map source file. If the directory for the desired map source file does not exist, then it is created. If creating the source map is successful, the pseudo map component is converted to a source map component (the icon color changes from pink to blue). You can now perform any action that is valid for a source map component - for example, opening the Map Designer and defining rules for the map.
  
  How to build maps in different environment?
  To run a map on another platform, you must build the map for that platform, using the Build for Specific Platform command. To run a map on another platform, that platform must have the Command Server installed. To identify which map is built for a specific platform, maps compiled for specific platforms are compiled with platform-specific file name extensions. The name of the platform-specific compiled map file is the executable map name with the platform-specific file name extension.
  
  For example, building the map MyMap for the MVS platform compiles the MyMap.mvs map. The platform-specific file name extensions prevent you from inadvertently overwriting your original compiled map and help identify which compiled map file should be transferred to the specific platform environment.
  
  Note Creating a folder exclusively for platform-specific maps is strongly recommended.
  
  The Build for Specific Platform command creates a compiled map file in the format required for a given platform, which accounts for byte-order and character set differences on that platform.
  
  To build a map for a specific platform
  
  1. Select the map you want to build.
  
  2. From the Map menu, choose Build for Specific Platform. The Select Platform dialog box appears.
  
  3. For the Platform, select the platform on which you plan to run the map.
  
  The File Name field on the Select Platform dialog box updates with the name of the compiled map that will be ported to that platform.
  
  4. Click OK.
  
  After the map is built for the specific platform, perform a binary file transfer of compiled map file to the command server environment. For example, in a UNIX environment, you might use FTP to transfer the ported map to your UNIX server.
  You should always use the Build for Specific Platform command when your target platform has a different byte order or character set than the one in your map development environment.
  
  What is workspace?
  
  What are the methods to override input/output settings? Using RUN function and IFD settings. Data sources and targets, and other map settings, can be overridden from the Integration Flow Designer or when a map is run using the command server or the Platform API.
  
  What is WorkArea?
  
  
  Versions change – Upgrading?
  Whenever you add a subsystem that references an .msd file from a previous version, a message notifies you that all map source files (.mms) will be updated unless the paths to the existing maps are changed by using the Find/Replace operation.
  Use the Find and Replace commands to change the paths that specify where executable maps are located on target servers.
  
  Note The text on the Find All button changes to Find when a value is entered in the Find What field.
  
  The Find dialog appears with the name of the active system displayed in the title bar.
  You can search for component names, card names, and path names.
  
  How to specify database as parameter of RUN Map?
  -ID1
  
  What are the adapters you have come across?
  Open to you (like FTP, Database, MQ, and File)
  
  What are the settings you have to do for DATABASE Adapter?
  1. From the input or output card(s) in the executable map, select Database as the value for either the GET > Source or PUT > Target settings.
  
  2. Select the .mdq file containing the database-specific source or target information.
  
  3. Perform the following for an input and/or an output card:
  
  § In an input card, select a query from the .mdq file.
  
  § In an output card, specify a table name or stored procedure.
  
  PFA the screen shot to know the basic setting details required for a database adapter.
  
  Do you have any external commit for DATABASE adapters?
  Yes we can have external commit
  
  81. During setting override operation what does “-ofb”?
  If the map, burst, or card does not complete successfully, roll back any changes made to this data target. If this option is not specified, the OnFailure setting compiled into the map is used.
  
  82. Is it possible to create a backup with map settings?
  Yes it is possible to create Backup for both the input and output cards. You can define the BACKUP settings for each input or output card needed.
  IF (PRESENT (A), A,B) what is the equivalent function? EITHER(A,B)
  
  84. What is EITHER function? The EITHER function returns the result of the first argument that does not evaluate to NONE.
  
  Syntax
  EITHER (single-general-expression { , single-general-expression } )
  Meaning EITHER (try this { , if none—try_this } )
  Returns
  This function returns a single-object. Returns try this, if try this does not evaluate to NONE. Returns if_none_try_this, if try this evaluates to NONE. Returns the next if_none_try_this, if the first if_none_try_this evaluates to NONE, and so on.
  
  Uses
  Use EITHER when you want a default when an expression evaluates to NONE and the expression may cause common arguments to produce an unintended result.
  
  85. Can you use LOOKUP in LOOKUP like LOOKUP (LOOKUP ())?
  Yes
  
  86. In a functional map if u are using 5 parameters, in that first parameter is EXTRACT () .If no values gets return for the EXTRACT, how will the functional map behave? The functional map will not be called.
  
  Can we refer to two different databases at a time?
  Yes we can refer to two different databases at a time by referring to two different mdq’s which has different oracle database settings
  
  
  Frequently used functions in Mercator
  
  
  Integration Flow Designer and Servers
  
  What is event server?
  The Event Server automates the execution of systems of maps and can control multiple systems.
  
  Different triggering events in msd?
  Source and Event Triggered
  
  What is command server?
  The Command Server is used to develop, test, and execute maps in development environments. It can also be used to execute commands in production environments but a single map at a time.
  
  Working of event server?
  The Event Server runs systems of maps that are created and generated using the Integration Flow Designer (IFD). These systems of maps that are generated specifically to run in the Event Server are called Event Server system files (.msl); sometimes referred to as Event Server control files. When the Event Server starts running, it is initialized with .msl files in the deployment directory.
  
  Stopping and starting of event server?
  start_es – will start the corresponding event server that is currently in use.
  Stop_es - will stop the event server that is currently under use.
  
  What is the purpose of event server?
  The Event Server automates the execution of systems of maps and can control multiple systems. On Windows platforms, the Event Server runs as a multi-threaded service. On UNIX platforms, the Event Server runs as a multi-threaded daemon.
  
  What is Event Server Path?
  Event Server Path is the path where Event server system files (.msl) are placed.
  
  Is it necessary to stop an event server when new system/changes to a system is deployed?
  Yes. Before you create or update an .msl file from the Integration Flow Designer (IFD), stop the Event Server and Event Server Monitor. If the Event Server is running when you create or update an .msl file, the change is not recognized and the file does not appear in the Event Server Monitor. You must restart the Event Server in order for changes to be recognized.
  
  Turning on off Trace file, how does it affect performance? It is recommended to turn off the trace file while executing in the server, since it takes time and space for generating and storing the trace file.
  
  What is the use of IFD?
  Use the IFD whenever you have multiple maps to manage within your enterprise. One click can build or port as many maps as you have defined in any system.
  
  Note You must use the IFD to generate systems if you plan to use the Event Server. The IFD is the client definition facility for the Event Server.
  
  You do not need the IFD if you are using a Command Server. However, you will find it to be useful as a client facility for managing maps that will be run by a Command Server. The IFD generates process control information for Command Servers in the form of command files. Generating these command files manually is tedious and error-prone. Using the IFD eliminates possible manual errors.
  
  What are the steps to create a *.msd file?
  The main function of the Integration Flow Designer (IFD) is to create system definition files (.msd) that are generated into Event Server system files (.msl).
  
  To create a new system definition file
  
  1. From the File menu, choose New.
  A new system definition file icon named SystemFileX (where X is a sequential number) appears in the Navigator and a new system window opens with the default name System1.
  
  You are now ready to begin creating the system definition diagram for your new system.
  
  To save a system definition file
  
  1. Select File > Save.
  2. Enter a file name for the new system definition file.
  3. Click Save.
  
  The new system definition file name is applied and the new name appears in the title bar of the active system window. The title bar of the system window displays the system name followed by the system definition file name in parentheses (*.msd). The settings for Server, Execution Mode, and Platform are set to the defaults until you change them.
  
  To create a system in an existing system definition file
  
  1. In the Navigator, select the system definition file that is to contain the new system.
  
  2. From the System menu, choose New.
  
  The New System dialog appears with a default name of System followed by a sequential number.
  
  3. Accept the default name or enter a unique name for the system, and click OK.
  
  A system window appears with the new system name and the path name of the system definition file displayed in the title bar. The new system name also appears in the List view of the Navigator.
  
  An msd is time event based. For example, From 10:00AM the map had to be triggered for every five minutes. A huge file A is present and it starts getting validated by 10:00AM and prolongs for more than 5 min .What will happen? Will the maps stops processing the current file and some more instance of the map will be triggered such that it takes the new files allowing the file A to get processed in parallel? Either the next time event (10:10) can be skipped or multiple instance of the map can be triggered to validate the new files. PFA the screen shot to accomplish the setting for this scenario
  
  99. Is it possible to set time and source event simultaneously? Yes it is possible to set. PFA the screen shot to accomplish this situation
  
  100. How will you use the event server?
  To use the Event Server, you must complete a series of steps. The list below provides a high-level overview of the steps to follow after installing Ascential DataStage™ TX.
  
  Basic Steps
  
  These steps assume that you have already generated an Event Server system file (
  .msl). For help on creating or generating a system file, refer to one of the following:
  
  ¨ Creating a System Definition File
  ¨ Generating System Files for the Event Server
  
  Before you create or update an .msl file from the Integration Flow Designer (IFD), stop the Event Server and Event Server Monitor. If the Event Server is running when you create or update an .msl file, the change is not recognized and the file does not appear in the Event Server Monitor. You must restart the Event Server in order for changes to be recognized.
  
  Steps for Using the Event Server
  
  ¨ Configure the Event Server from the Event Server Administration interface.
  ¨ Start the Event Server service.
  ¨ Configure an Event Server connection in the Management Console and begin viewing statistical data from the process running. (From there you can also control the compound system that is running).
  ¨ To view the watches run dynamically and to take snapshots, use the Event Server Monitor.
  ¨To view snapshots captured by the Event Server Monitor, use the Snapshot Viewer.
  
  Database Interface Designer
  
  101. Specifying mdq’s in maps?
  Dynamic and Static mdqs
  Static: mdq will be specified in input path and database access happens only 1 time.
  Dynamic: Through DBQUERY and DBLOOKUP
  
  102. What is the use of Database Interface Designer
  The Database Interface Designer is used to:
  
  ¨ specify the databases to use for a source or target
  ¨ define query statements
  ¨ automatically generate type trees for queries or tables
  
  103. What are the steps to create a *.mdq file?
  A database/query file contains the definitions for one or more databases as well as queries, stored procedures, and other specifications that may contribute to the execution of a map. A database/query file is a file you create and save using the commands on the File menu in the Database Interface Designer. The result is a file with an extension of .mdq. This file name (including its path) appears in the title bar of the Database Interface Designer window when it is the selected file in the Navigator, indicating that it is the active .mdq file.
  
  After starting the Database Interface Designer, the Navigator lists one or more .mdq files depending upon whether you selected to create a new .mdq file or to open one or more existing files. When an .mdq file is created, it appears in the Navigator next to the appropriate icon (). The default name is Database_QueryFile that is followed by an assigned, sequential number. To change this name, from the File menu, select Save As to save the new .mdq file, specifying the file name and location as desired.
  
  Note Saving a new .mdq file uses the same procedure as saving an existing one.
  
  
  Type Designer
  
  1) What is a Type Designer?
  The Type Designer is used to define, modify, and view type trees.
  
  2) What is syntax?
  The syntax of data refers to its format including tags, delimiters, terminators, and other characters that separate or identify sections of data.
  
  3) What is structure?
  The structure of data refers to its composition including repeating sub-structures and nested groupings.
  
  4) What is semantics?
  The semantics of data refer to the meaning of the data including rules for data values, relationships among parts of a large data object, and error detection and recovery.
  
  5) What is a type tree?
  · A type tree describes the syntax, structure, and semantics of your data.
  · A type tree (.mtt) defines the entire contents of at least one input that you intend to map or one output you intend to map.
  · A type tree is the mechanism for defining each element of your data. Similar to a data dictionary, a type tree contains a collection of type definitions.
  
  6) Give small example.
  A data file is a simple example. The file is made up of records and each record is made up of fields. In this case, there are three kinds of data objects: a file, a record, and a field.
  
  7) Mention the different type designer files.
  Extension File type
  .mtt Type tree file
  .dbe Type tree analysis message file
  .bak Backup type tree file
  
  7) Mention the type designer icons.
  Icon Description
  Circle (blue) Item type
  Circle (green) Sequence group type
  Triangle Choice group type
  rhombus Partitioned group
  double plus Unordered group
  circle (red) Category type
  
  
  8) What are the different windows in type tree.
  · Item Window
  · Group Window
  · Category Window
  · Properties Window
  
  9) Difference between Group and Category window.
  · The group window is used to define the components of the group type. Group types represent objects composed of other objects.
  · The category window is used to define the components of the category type. category type that are used for inheritance purposes, to make components available to other types.
  · Group window has a rule column for entering component rules.
  · Components of a category do not have component rules.
  
  10) What is the use of properties window.
  The Properties window is used to define and view the properties of the currently selected type. Each type has properties that define the characteristics of that data object.
  
  11) Mention the steps for creating type trees.
  The following list outlines the process for creating type trees:
  · Identify the data objects in your data and define each piece of data
  that you intend to map.
  · Create types for each data object in your data.
  · Define the properties of each type.
  · Create component lists.
  · Define component rules, if needed.
  · Define item restrictions, if needed.
  · Analyze and save the tree.
  
  12) What is a component.
  A component is an object that is part of a larger object.
  
  13) What is a data object.
  · A data object is a complete unit that exists in your input or is built on output.
  · A data object may be simple (such as a date) or complex (such as a purchase order).
  · A data object is some portion of data in a data stream that can be recognized as belonging to a specific type.
  
  14) What is a type.
  · A type defines a set of data objects that have the same characteristics.
  · For example, the type Date may be defined as representing data objects in the form MM-DD-YY.
  · The type Customer Record may be defined as representing data objects, each of which consists of a Company, Address, and Phone data object.
  
  15) What are the different classes of type.
  · Item
  · Group
  · Category
  
  16) What is an item?
  An item type represents a simple data object that does NOT consist of other objects.
  
  17) What is a group?
  A group type represents a complex data object that consists of other objects.
  
  18) What is a category?
  A category type is used for inheritance and for organizing other types in a type tree.
  
  19) When can two type trees be different.
  Two type trees are considered different if:
  · Any of the types are different.
  · Any of the types that exist in one type tree does not exist in the second type tree.
  · When the order of the subtypes within a subtype is different.
  
  20) When can two types be different?
  A type is different if:
  · Any of the properties are different
  · Any of the components are different
  · Any of the restrictions are different
  
  21) When can two restrictions be different?
  A restriction is different if:
  · The restriction value is different
  · The description is different
  
  22) What are the common properties for the Item types.
  For Item types, properties define whether the item is text, a number, a date & time or a syntax value. Properties include such characteristics as size, pad characters and justification.
  
  23) What are the common properties for the Group types.
  For Group types the properties are related to the format of that group. The format of a group may be explicit or implicit. In addition, type properties include syntax objects that appear at the beginning or end of the object as well as release characters.
  
  24) Mention some basic type properties.
  1. Name -> name of the type.
  2. Class -> class of the type whether it is category, group or item.
  3. Description -> to record a brief description of the type.
  4. Intent -> indicates whether the type is general type or xml type.
  5. Partitioned -> yes/no
  6. Order Subtypes -> choose the method in which the subtypes of this will be added or viewed in the type tree. Some of its methods are Ascending (default), Descending, Add First, Add Last.
  7. Initiator -> a syntax object that appears at the beginning of a data object. Its properties are none(default) , literal , variable.
  8. Terminator -> a syntax object that appears at the end of a data object. Its properties are none(default) , literal , variable.
  9. Release Characters - > it is a one byte character in the data indicating that the character(s) following it should be interpreted as data, but not as a syntax object. The release character is not treated as data, but the data that follows it is treated as actual data. Its properties are none (default), literal, variable.
  10. Empty -> the empty property provides alternate type syntax for groups or items when they have no data content. When the Empty property is specified for a type and there is no datacontent, the Empty syntax appears. For example, this can be used for XML data that contains either start and end tags or an empty tag.You can use the Empty type property instead of syntax object items to potentially improve the type tree run-time processing time (during data validation).
  
  25) Mention Item class properties.
  1. Item Subclass -> Number/Text/Date & Time/Syntax
  2. Interpret as -> Character/Binary
  3. Presentation -> Integer/Float/Packed/BCD
  4. Length (if binary only) ->1,2,3,4(default)
  5. Size -> min/max
  6. Separators -> yes/no
  7. Pad -> yes/no value =0(default for num) value=space (default for char)
  8. Padded to -> min content/fixed size length=0 (default)
  9. Justify -> left(default)/right
  10. Apply pad - > Fixed Group(default)/Any context
  
  26 ) What do you know about binary text items and number items.
  · Binary text items have content size and pad properties.
  · Binary data is required to be sized or of a fixed size.
  · Binary number items interpret the data as a byte stream.
  
  27 ) What do you know about character text items and number items.
  · Character text items can have content size and pad properties.
  · Character number items interpret the data as symbolic data.
  
  28) What is the content size.
  The content size of a text item specifies the bytes of data, excluding any initiator, terminator, release characters, and pad characters. It is also independent of the character set.
  
  29) What is Padding or Pad property.
  If the data value to be mapped to the target item is smaller than the minimum length of that item, pad characters are used to pad the data to that minimum length. Input data may contain both content and pad characters. Output data is built according to the pad definitions of the types.
  
  30) What are the different Pad properties.
  1. Pad > Value
  2. Pad > Padded to
  3. Pad > Justify
  4. Pad > Apply Pad
  
  1. Pad > Value -> To define the one byte pad character. The default value is 0.
  2. Pad > Padded to -> To define whether the data item is padded to fixed size or to the minimum content size defined for that item. The padded to length must be greater than or equal to the max size value.
  3. Pad > Justify - > To specify whether the data is padded to left or right.
  4. Pad > Apply pad -> To specify when to apply the pad character.
  
  31) What do you know about syntax objects properties.
  Syntax objects are characters that precede, separate or follow a particular data object.
  
  32) What are item restrictions and how are they grouped.
  Restrictions of an item type are the valid or invalid values for that item. For eg, the unit of measure field in the data must be one of a set values : CN,BX,PK,BR. These values should be defined as “include” restrictions of the item Unit of measure.
  Item restrictions are grouped into three categories Value, Character and Range.
  33) What are the rule properties for Value restrictions.
  Include and Exclude.
  
  34) What are the rule properties for Character restrictions.
  Include First, Include After, Exclude, Reference String.
  
  35) What are the rule properties for Range restrictions.
  Include Minimum, Include Maximum, Description and Exclude Minimum, Exclude Maximum, and Description.
  
  36) What is a sequence group type.
  A sequence group is a group in which all components are sequentially ordered.
  Each component of a sequence group is validated sequentially. It is mainly used when we want to get the output in the same order as the input.
  For e.g., in any EDI input file the elements of the control segments (ISA, GS, ST) are sequentially ordered.
  
  37) What is a choice group type.
  Choice groups provide the ability to define a selection from a set of components like multiple-choice questions on a test. A choice group is validated as only one of its components. Validation of choice group is attempted in the order of components until a single component is validated. If the choice group has initiator, the initiator is validated first. Choice groups have no partition or format properties. Components of a choice group must be distinguishable from each other. The components of a choice group cannot have a component range other than (1:1). Only one component of a choice group is built in the data.
  For e.g., the data type Record is a group subclass of choice. The group type record has three components Order, Invoice and Sales. The data validation of record will be only one of the components Order, Invoice or Sales.
  
  38) What is unordered group type.
  An unordered group has one or more components that can appear in the data stream in any order. Unordered groups have no partioned property. They have implicit format properties with syntax as none and delimited. When a group is defined as unordered, any component can appear in the data stream. A component can be an item or a group.
  Unordered group components have a range property. For example, if the unordered group, A, has the following component list: B (1:S) C D (S) then A must have one C, at least one B, and possibly some Ds. They could appear in any order. For example, data for A could have the pattern: CDDBDDD or BBBDDCBD.
  
  39) Difference between choice group and partitioned group.
  A choice group can have both items and groups as components whereas a partioned sequence group can have only group sub types.
  
  40) Difference between sequence and choice groups.
  Choice groups have no Partition or Format properties.
  
  41) Difference between explicit and implicit formats.
  The explicit format relies on syntax to separate components. Each component can be identified by its position or by a delimiter in the data. Delimiters appear for missing components.
  The implicit format relies on the properties of the component types. The format is not fixed. If delimiters separate components, they do not appear for missing components.
  42) What is Fixed Syntax.
  Fixed Syntax is the property for which a group data object has always the same size. Each component of a fixed group must be fixed. If you break down a fixed group, it ultimately consists of items that are fixed. Each is padded to a fixed size or its minimum and maximum content size are equal. Do not specify the size of a fixed group. The size is automatically calculated based on the size of the group’s components.
  
  43) What is Explicit Delimited Syntax.
  An explicit format group with a delimited syntax is one whose components are separated by a delimiter and the delimiter appears as a placeholder even when a component has no content. The only time a delimiter can be missing is if components following the delimiter are all optional and there is no data for these optional components.
  
  44) What is Floating Component?
  The floating component represents an object that may appear after any component of the group. An implicit group can have a floating component; an explicit group cannot. If the group is prefix or infix delimited, the floating component appears before the delimiter. If the group is postfix delimited, the floating component appears after the delimiter. A floating component can be an optional component that may appear after any other component. However, it is not included in the component list because it does not appear at a specific location. If a group has a floating component, a component must be distinguishable from a floating component. For example, components and floating component could start with different initiators.
  
  45) What is Implicit Delimited Syntax.
  If a delimiter separates the components of a group, but the delimiter does not appear when a component is missing that group has an implicit format, with a delimited syntax.
  
  46) What is a component range. Give some examples.
  The range defines the number of consecutive occurrences of that component. A component range can be specified for any component. A component range defines the number of occurrences.
  Syntax: component (min: max)
  Examples: 1) Record (1:s)
  2) Record (0:s) or Record(s)
  3) Record (1:6)
  4) Record (8)
  
  47) What is a component rule? Give some examples.
  A component rule is an expression about one or more components. It indicates what must be true for that component to be valid. For given data, it evaluates to either TRUE or FALSE. A component rule is similar to a test. If the data does not pass the test, it is invalid.
  Component rules are used for validating data.
  Examples: 1) Quantity < 1000 2) When (PRESENT (Address Field), PRESENT (Qualifier Field)) 3) Ammount = Quantity * Price 48) How can you enter an object name into the component rule. This can be possible by pressing ALT and dragging the object into the edit window. 49) What is the $ symbol in the component rule. The $ symbol is the short hand notation and it represents the current object or component itself. 48) Mention the component attributes. Component attributes are toggle commands. Three attributes can be assigned to a component in a component list: · Identifier · Restart · Sized 49) What is an Identifier Attribute. The identifier attribute can be used on a component of a group. The identifier indicates the components that can be used to identify the type to which a data object belongs. All the components, from the first, up to and including the component with the identifier attribute, are used for type identification. 50) What is Restart Attribute. To continue processing your input data when a data object of a component is invalid, assign the restart attribute to that component. 51) What is Sized Attribute. The sized attribute is used on a component in which the value specifies the size (in bytes) of the component immediately following it. The sized attribute can be used on more than one component of a group. 52) What is Partitioning in Mercator and when it is required. Partitioning is the method of subdividing objects into mutually exclusive subtypes. Partitioning is required when components are randomly or partially ordered. Partitioning is also used to simplify the rules needed in the map or to build additional logic into the definition of your data. 53) Explain the concept of partitioning with good example. Consider an Employee type tree. It is having multiple departments. Development, Testing, Production and maintenance. In the rule without partition, you would specify a condition for each department abbreviation in each department. This could make your mapping rules long, difficult to read and difficult to maintain. Map rule without partitioning =IF (Department Field:.: Input = “DE” Department Field:.: Input = “DB” Department Field:.: Input = “DA” Department Field:.: Input = “DS” , F_MapDevelopment (Record: Input), NONE) Map rule with partitioning The mapping rule with partition is more concise, self-documenting and easier to maintain. Here we set the Department partition properties to YES. =F_MapDevelopment (EXTRACT (Record:Input, PARTITION (Department Field :.:Input, Development))) 54) What are the benefits of Partitioning. · The rule is shorter than the rule without partitioning. · It is easy to read this map rule and understand the mapping function being performed. · The partitioning method is easier to maintain. · Partitioning using a restriction list used with Ignore Case setting eliminates the need of PROPER, LOWERCASE, UPPERCASE functions. 55) What are the three methods to partition items in type trees. · Initiators. · Restrictions. · Format. 56) What are the three methods to partition Groups in type trees. · Initiators. · Identifiers. · Component Rules. 57) How can you validate the type tree definition or data type definition. During map execution, the input data is compared to the data definition in the type tree. If the data does not match the definition, it is invalid or in error. To validate a data object as belonging to a certain type, the data must be matched to its type definition. For the data to be valid, the following must be true. · The data must have the properties defined in the properties window. · If the type is an item that has restrictions, the data object must match one of the restrictions. · If the type is a group, the components of the data object must match those defined in the group window, and each component rule must evaluate to TRUE at map execution time. 58) What is UFO. UFO(Unidentified Foreign Obj) is data in error with no valid data contained within it. 59) How can you handle errors in the data stream. The restart attribute provides instructions for handling errors encountered in a data stream. If you are mapping data of a component with a restart attribute only the valid occurrences of that component are mapped. For example, your input is a file of records and the record component of File has the restart attribute and some of the records are invalid. When you map the Record objects, only the valid records are mapped. To map the invalid records use the Reject function. 60) How the Restart Attribute Works. The restart attribute has the following properties · During validation, the restart attribute is used to tell the system where to start over when an UFO is encountered in the data. All unrecognized data is considered to be an error of the type with the restart assigned. · The restart attribute is used during validation to mark both UFOs and existing data objects in error that are ignored when mapping input to output. · The restart attribute is used to identify valid data objects that contain objects in error. · If an invalid data object is a component that does not have the restart attribute, that component is marked in error. · If components, from the beginning of the data are marked in error because none of them has a restart, the system stops after validation. It does not map the input data to the output. 61) What is Type Tree Analyzer. The Type Tree Analyzer analyzes type definitions and ensures internal consistency. The Analyzer checks your data definitions for logical consistency. It does not compare your definitions to your actual data. The resulting analyzer messages indicate whether your type tree definitions are acceptable or whether they match your data. 62) What is Logical Analysis. Logical Analysis addresses the integrity of the relationships that you define. Logical Analysis detects the following · Undefined components · Components that are not distinguishable from one another · Item restrictions that do not match the properties of that item · Circular type definitions · Checks delimiters relationships to each other and to components · Undefined inherited relationships · Logical errors contained in component rules 63) What is Structural Analysis. Structural Analysis addresses the integrity of the underlying database. It may be able to detect and possibly correct defects caused by system environment failures.