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InterSystems IRIS Data Platform 2019.2  /  Class Definition Reference

Class Definition Reference
Identity
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Specifies whether this property corresponds to the identity column in the corresponding SQL table. Applies to persistent classes.
Usage
To specify that this property corresponds to the identity column in the corresponding SQL table, use the following syntax:
Property name As %Integer [ Identity ];
Note:
The type of the property can be any integer type, for example, %BigInt, %Integer, %SmallInt, or %TinyInt.
Otherwise, omit this keyword or place the word Not immediately before the keyword.
Details
For a persistent object, this keyword specifies that a property corresponds to an identity column in the corresponding SQL table (that is, a column that is marked with the SQL IDENTITY keyword). This keyword is useful particularly for tables that are created through DDL statements. When creating a table using DDL, make sure that any IDENTITY field is defined with MINVAL=1, if possible, to allow the creation of a bitmap extent index. See “CREATE TABLE” in the InterSystems SQL Reference.
Default
If you omit this keyword, this property is not used as the identity column.
See Also


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Content Date/Time: 2019-08-22 06:48:58