sql - Access 2010 Query Confusion -

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just need quick clarification

i have 2 queries in access database should return inverse results:

select equipment.title equipment (((equipment.[equipmentid]) not in (      select equipmentid     downperiod     update null )));

the 2nd excludes not before in. confusion comes fact query posted above not return results if equipmentid field has @ least 1 null value in downperiod table.

it works fine if fields filled, , inverse query list works. makes me think there's issue null value.

now field should never null wanted know if still work in unlikely event null did occur.

thank in advanced!

try joins:

select equipment.title equipment inner join downperiod on equipment.equipmentid = downperiod.equipmentid downperiod.update null

and

select equipment.title equipment inner join downperiod on equipment.equipmentid = downperiod.equipmentid downperiod.update not null

see if change in syntax fixes issue.

not should work, believe faster practise using in() not in() methods (might wrong on that, looks nicer read). adds ability change "is not null" criteria same in->not in


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