我认为会更好
SELECT COUNT(*)
FROM TABLE1
WHERE NOT EXISTS (SELECT Table1Id FROM TABLE2 WHERE TABLE2.Table1Id = TABLE1.Table1Id AND UserID = 1)
我也将检查索引,如ck建议
SQL查询帮助
我认为会更好
SELECT COUNT(*)
FROM TABLE1
WHERE NOT EXISTS (SELECT Table1Id FROM TABLE2 WHERE TABLE2.Table1Id = TABLE1.Table1Id AND UserID = 1)
我也将检查索引,如ck建议