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Seleziona i valori da un elenco che non sono in una tabella

Una tabella temporanea è la soluzione migliore, ma se non è possibile, puoi modificare una tabella temporanea selezionando le costanti e unendole insieme.

Usando questa soluzione puoi fare quanto segue:-

SELECT i
FROM 
(
    SELECT 1 AS i UNION SELECT 2 UNION SELECT 3 UNION SELECT 6 UNION SELECT 7
) AS mylistofids 
LEFT JOIN mytable
ON mytable.id = i
WHERE mytable.id IS NULL;

Puoi anche generare una vasta gamma di numeri (supponendo che tu abbia a che fare con ID interi) incrociando intervalli di numeri. Quindi scegli quelli che sono nella clausola IN:-

SELECT i
FROM 
(
    SELECT units.i + tens.i * 10 + hundreds.i * 100 + thousands.i * 1000 + tensthousands.i * 10000 AS i
    FROM (SELECT 1 AS i UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION SELECT 0 ) AS units
    CROSS JOIN (SELECT 1 AS i UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION SELECT 0 ) AS tens
    CROSS JOIN (SELECT 1 AS i UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION SELECT 0 ) AS hundreds
    CROSS JOIN (SELECT 1 AS i UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION SELECT 0 ) AS thousands
    CROSS JOIN (SELECT 1 AS i UNION SELECT 2 UNION SELECT 3 UNION SELECT 4 UNION SELECT 5 UNION SELECT 6 UNION SELECT 7 UNION SELECT 8 UNION SELECT 9 UNION SELECT 0 ) AS tensthousands
) AS mylistofids 
LEFT JOIN mytable
ON mytable.id = i
WHERE mylistofids.i IN (1, 2, 3, 6, 7)
AND mytable.id IS NULL;