I would like to check streets using a table.
- the query is not optimal
- the query takes much too long
Can someone help me
SELECT id, strasse, plz
FROM `adress`
WHERE strasse NOT IN (
SELECT street
FROM post_plz
WHERE `street` like adress.strasse AND plz like adress.plz
)
LIMIT 5;
CodePudding user response:
You could try using aleft join between the table and check for not mactching values
SELECT id, strasse, plz
from `adress`
left join post_plz on strasse = street
AND `street` like adress.strasse
AND plz like adress.plz
WHERE street is null
LIMIT 5;
CodePudding user response:
SELECT id, strasse, plz
FROM adress
WHERE NOT EXISTS ( SELECT NULL
FROM post_plz
WHERE post_plz.street = adress.strasse
AND post_plz.plz = adress.plz )
-- ORDER BY {expression}
LIMIT 5
Without ORDER BY the query returns non-deterministic output (two query executions may produce different outputs). So it is strongly recommended to add some rows ordering.
The indices post_plz (adress, plz)
and adress (strasse, plz, id)
must improve.