postgres

Commit Graph

Author	SHA1	Message	Date
Tom Lane	0cb65564e5	Add exclusion constraints, which generalize the concept of uniqueness to support any indexable commutative operator, not just equality. Two rows violate the exclusion constraint if "row1.col OP row2.col" is TRUE for each of the columns in the constraint. Jeff Davis, reviewed by Robert Haas	16 years ago
Tom Lane	25d9bf2e3e	Support deferrable uniqueness constraints. The current implementation fires an AFTER ROW trigger for each tuple that looks like it might be non-unique according to the index contents at the time of insertion. This works well as long as there aren't many conflicts, but won't scale to massive unique-key reassignments. Improving that case is a TODO item. Dean Rasheed	17 years ago

Author

SHA1

Message

Date

Tom Lane

0cb65564e5

Add exclusion constraints, which generalize the concept of uniqueness to

support any indexable commutative operator, not just equality.  Two rows
violate the exclusion constraint if "row1.col OP row2.col" is TRUE for
each of the columns in the constraint.

Jeff Davis, reviewed by Robert Haas

16 years ago

Tom Lane

25d9bf2e3e

Support deferrable uniqueness constraints.

The current implementation fires an AFTER ROW trigger for each tuple that
looks like it might be non-unique according to the index contents at the
time of insertion.  This works well as long as there aren't many conflicts,
but won't scale to massive unique-key reassignments.  Improving that case
is a TODO item.

Dean Rasheed

17 years ago

2 Commits (8292079ad3db05faff01d03c7a8646704edbf54b)