topic Re: Exist function in QlikView

Exist function

lionking15 — Wed, 25 Nov 2020 16:16:04 GMT

can anyone explain me what exactly happens we use exists or not exists function with two parameters???

Thanks!!!

Re: Exist function

MindaugasBacius — Tue, 20 Sep 2016 05:02:47 GMT

I would explain it like this:

EXISTS(where to look, what to look).

Re: Exist function

Digvijay_Singh — Tue, 20 Sep 2016 05:22:57 GMT

Many things can happen based on available data model such as -

1. Exists with single parameter can load QVD in optimized load,with two parameters it loads QVD in bit slow/standard mode.

2. Exists(Single Field) looks the values in symbol table so totally independent of specific tables loaded, if you want comparison with a specific table, you may want to rename the loaded field to tempfield(so it links to only one table) in that table and then use ( Where exists(tempfield,newlyloadedfield) while loading new table, the search here as well happens in symbol table but into the tempfield symbol table which we know available in single table only.

3. Where not exists(single field), it cannot load duplicate values, because 2nd and later comparisons will fail as value already exists in symbol table.

Re: Exist function

Anonymous — Tue, 20 Sep 2016 05:22:59 GMT

Hi,

Please see this thread: Understanding EXISTS() function - Qlikview vs SQL/RDBMS