Comments - CHECK constraint introduced, when make it really useful?
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Simple Example which makes sure there are no entries inserted or updated which have overlapping time spans. Most important: This solution should be thread safe: CREATE TABLE Test ( startTime bigint(20), stopTime bigint(20), CONSTRAINT overlapping CHECK ( (SELECT COUNT(*) FROM Test r WHERE r.startTime < stopTime AND r.endTime > startTime LIMIT 1) = 0 ) ); Even more elegant would it be to put the CHECK content into a function. But I consider that to be a luxury.
And: According to JIRA Bug https://jira.mariadb.org/browse/MCOL-935 CHECK is even not working for UPDATE, only for INSERT. Although the documentation tells otherwise.