PostgreSQL 'NOT IN' and subquery
When using NOT IN you should ensure that none of the values are NULL:
SELECT mac, creation_date
FROM logs
WHERE logs_type_id=11
AND mac NOT IN (
SELECT mac
FROM consols
WHERE mac IS NOT NULL -- add this
)
You could also use a LEFT JOIN and IS NULL condition:
SELECT
mac,
creation_date
FROM
logs
LEFT JOIN consols ON logs.mac = consols.mac
WHERE
logs_type_id=11
AND
consols.mac IS NULL;
An index on the "mac" columns might improve performance.
When using NOT IN, you should also consider NOT EXISTS, which handles the null cases silently. See also PostgreSQL Wiki
SELECT mac, creation_date
FROM logs lo
WHERE logs_type_id=11
AND NOT EXISTS (
SELECT *
FROM consols nx
WHERE nx.mac = lo.mac
);