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InterSystems IRIS Data Platform 2019.2  /  Class Definition Reference

Class Definition Reference
PrimaryKey
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Specifies whether this index defines the primary key for the table.
Usage
To specify that the primary key for this table is formed by the properties on which this index is based, use the following syntax:
Index name On property_expression_list [ PrimaryKey ];
Otherwise, omit this keyword or place the word Not immediately before the keyword.
Details
This keyword specifies that this index should be reported, via SQL, as being the primary key for this class (table).
A PrimaryKey index also behaves like a unique index. That is, for the property (or the combination of properties) that you use in this index, InterSystems IRIS enforces uniqueness. It is permitted, but redundant, to specify the Unique keyword as true in this index definition.
Example
Index EmpIDX On EmployeeID [ PrimaryKey] ;
Default
If you omit this keyword, the primary key for this table is not formed by the properties on which this index is based.
See Also


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Content Date/Time: 2019-08-23 06:48:00