如何使用 EXISTS 關鍵字驗證兩個表中是否存在匹配值？

select * from table1 where exists (     select *     from table2     where table1.column_name = table2.column_name );

SELECT * FROM (     SELECT pn_Code, serialNumber     FROM pnassertbasic_ruku pr     LEFT JOIN pnassertruku pu ON pr.parent_pnAssertRuku_id = pu.child_pnAssertRukuDetails_id     WHERE pn_Code IS NOT NULL AND serialNumber IS NOT NULL AND DATE(pr.create_time) = CURDATE() AND pr.warehouseEntryNumber <> 'WEd3791f0b' ) AS temp1 WHERE EXISTS (     SELECT *     FROM (         SELECT pn_Code, serialNumber         FROM pnassertbasic_ruku pr         LEFT JOIN pnassertruku pu ON pr.parent_pnAssertRuku_id = pu.child_pnAssertRukuDetails_id         WHERE pu.child_pnAssertRukuDetails_id IS NULL AND pr.warehouseEntryNumber = 'WEd3791f0b'     ) AS temp2     WHERE temp1.pn_Code = temp2.pn_Code AND temp1.serialNumber = temp2.serialNumber );