How to filter 2 tables with the help of another one ?

[#1]

Hi,

I've Three tables : TableA, TableB, TableC. They have a common field : KeyField.

I want to keep only lines of TableB and TableC where KeyField value exist in TableA.
My question is what is the best solution to do it ?

The only way I found, for the moment is to use :

Load * From TableA

Left Keep
Load * From TableB

Temp:
Noconcatenate Load * resident TableA
Left Keep Load * From TableC

Drop Table Temp;

It works, but I think it's a bit complex (and not optimized).

Is someone have a better idea ?

Thanks

Best regards

[Oleg_Troyansky · Accepted solution]

You can specify TableA in your left keep, which eliminates the need in loading it twice:

left keep (TableA) load ...

cheers,

[johnw]

LOAD * FROM TableA;
LOAD * FROM TableB WHERE EXISTS(KeyField);
LOAD * FROM TableC WHERE EXISTS(KeyField);

Or have I misunderstood the requirement?

[#4]

Thanks,

That's exactly the answers I need !

Regards