Is there a way to create a unique constraint over multiple columns like in Mysql?
UNIQUE KEY `uniqueKey` (`Field1`,`Field2`),
The only thing i have found is the unique keyword directly after the field.
Thanks in advance!
You should be able to add a unique constraint as:
ALTER TABLE t ADD CONSTRAINT unq_field1_field2 UNIQUE(field1, field2)
As with other databases, this is almost exactly equivalent to creating an index. The difference is that the constraint is named -- which can be convenient for tracking constraints and understanding error messages.
Notice, that if the matching index does not exist, then a unique index is automatically created.
You should be able to create a multi-column index
CREATE UNIQUE INDEX myindex
ON mytable (col1, col2 desc, col3)
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