Ab Initio Component | JOIN : Part 1

 Purpose of JOIN Components

• JOIN  is used to reads data from two or more input ports, combines records with matching keys according to the transform you specify, and sends the transformed records to the output port.

•  Its additional ports caln also be used to collect rejected and unused records.  

 

Parameters for JOIN (Not all parameters are covered.)

count (integer, required)

• It is an integer n specifying the total number of inputs (in ports) to join. The number of input ports also determines the number of the following ports and parameters:

        unused ports

        reject ports

        error ports

        record-match-required parameters

        dedup parameters

        select parameters

        override-key parameters

    Default is 2.

    Each in port (always two or more) has a number n appended. Each outn, unusedn, rejectn, and errorn port corresponds to an inn port.

 

 

sorted-input (boolean, required)

• When this parameter is set to False, the component accepts unsorted input and permits the use of the maintain-order parameter.

• When this parameter is set to True, the component requires sorted input .In this case, consider setting the check-sort parameter to True.

    Default is True. 

key(key specifier, required)

 

• Name(s) of the field(s) in the input records that must have matching values for JOIN to call the transform function. The types of the fields in the different inputs must be compatible; 

 

transform (filename or string, required)

• Either the name of the file containing the transform function, or a transform string. 

 join-type (choice, required)

    You have to  choose one of the option  from the following:

• Inner join (default) — Sets the record-match-requiredn parameters for all ports to True. The GDE does not display the record-match-requiredn parameters, because they all have the same value.

•  Outer join — Sets the record-match-requiredn parameters for all ports to False. The GDE does not display the record-match-requiredn parameters, because they all have the same value.

•  Explicit — Allows you to set the record-match-requiredn parameter for each port individually.

    If you set the dedupn parameter to True on the driving input, set the join-type parameter to Inner join. (The driving input is the largest input, as specified by the driving parameter.)

    If you remove duplicates on this input port before joining it to the driving input, set the record-match-requiredn parameter to True on all other ports.

 

 

parameter-interface (choice, required)

• This parameter is available only after you update a pre-Version 3.2.1 JOIN component to Version 3.2.2 or higher. It is not available for new components.

• Controls whether to use a legacy or improved parameter interface. The choices are the following:

•  legacy — Displays the record-requiredn parameter whose boolean value specifies whether to use an inner or outer join and whether a record is required or substitute a null for missing records. This parameter has inverted booleans. The default for pre-Version 3.2.1 components.

• version-3-2-2 — Displays the record-match-requiredn parameter whose boolean value specifies whether to use an inner or outer join. This parameter has normal booleans