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Options to Use a Predefined One-to-One Extension Table

Siebel CRM uses one-to-one predefined extension tables for many of the predefined data tables. The predefined extension table contains columns of various types that possess a predefined one-to-one relationship with a base table. This base table uses more columns in the extension table for new functionality without altering the base table or modifying the database schema. For more information, see Guidelines for Modifying a Predefined One-to-One Extension Table.

A one-to-one predefined extension table does not require you to create a new business component because Siebel CRM implicitly defines this type of table as a join. For more information about implicit joins, see How an Extension Table Stores Custom Data.

A one-to-one predefined extension table includes an _X suffix, such as S_PROD_INT_X. Siebel CRM names columns in these tables with ATTRIB_nn, where nn is a value from 01 to 47.

Table 10 lists the different data types in a Siebel extension table and the number of columns of each data type.

Determining Availability of a Predefined Extension Column

Before you use a predefined extension table you must determine if a predefined Siebel application uses or does not use the table column. To do this, you search the Siebel repository for fields that are associated with the column.

CAUTION:  If a field that Siebel CRM defines references a column, then do not deactivate the field to use the column for another purpose.

To determine availability of a predefined extension column

1. In Siebel Tools, in the Object Explorer, click the Flat tab.
2. In the Object Explorer, click Field.
3. In the Fields list, issue a query using values from the following table.

   Property	Value
   Column	Name of the column you must use.
   Join	Name of the extension table you must use.

4. If the query does not return any Field object definitions, then Siebel CRM does not use the column in the extension table and it is available.
5. If the query returns one or more object definitions, find another extension column in that table. To determine which extension columns are currently in use, perform the query again using values from the following table.

   Property	Value
   Column	ATTRIB*
   Join	Name of the extension table you must use.