I'm wondering if there's an ideal way to improve the efficiency of this query:
SELECT i.id FROM items i
WHERE (NOT (EXISTS (SELECT c.id
FROM contacts c WHERE (c.id = i.id))));
It takes a while to execute, clearly. Thank you,
SELECT i.id FROM items i
WHERE (NOT (EXISTS (SELECT c.id
FROM contacts c WHERE (c.id = i.id))));
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