topic Re: Incremental load with Composite key in QlikView

Incremental load with Composite key

prabhu0505 — Fri, 30 May 2014 18:30:52 GMT

Hi All,

I want to implement incremental load with composite key, pls. give me suggestions.

Composite Key : Fields A, B, C, D make up the key. Here C is date Field.

Logic: Only Insert and Update. No Delete.

Thanks..

Re: Incremental load with Composite key

mdmukramali — Fri, 30 May 2014 19:15:20 GMT

Dear,

Please can you attach some sample data.

Thanks,

Mukram

Re: Incremental load with Composite key

prabhu0505 — Fri, 30 May 2014 19:22:01 GMT

A	B	C	D	E	F
a1	b1	1/1/2014	d1	10	25
a1	b1	1/2/2014	d1	10	15
a1	b1	1/3/2014	d1	20	30
a1	b1	1/3/2014	d11	30	35
a2	b2	1/1/2014	d2	40	45
a2	b21	1/1/2014	d2	20	55
a21	b2	1/1/2014	d2	15	65

Re: Re: Incremental load with Composite key

maxgro — Fri, 30 May 2014 20:19:08 GMT

you can find some help in online help

see attachment

Re: Re: Incremental load with Composite key

prabhu0505 — Fri, 30 May 2014 20:32:47 GMT

Hi Massimo,

I've currently 1 million record in the table expecting it to grow till 2 million within a year. So using string concatenation (A&'-'&B&'..) will degrade the performance? Any other alternatives?

Thanks..

Re: Incremental load with Composite key

maxgro — Fri, 30 May 2014 20:56:50 GMT

- autonumberhash... instead of concat (some goods readings on qlikviewnotes and qlikfix)

- store the primarykey calculated field in the qvd: you don't need to recalculate it every run

- some millions of records? don't think they are a big number; but you can try to simulate the performance before

Re: Incremental load with Composite key

prabhu0505 — Fri, 30 May 2014 21:38:36 GMT

My doubt is whether Autonumberhash will generate same key based on the combination of column.

Autonumberhash('a1','b1','01/01/2014',d1) will be same every time.

Re: Incremental load with Composite key

maxgro — Fri, 30 May 2014 22:28:23 GMT

- hash is hash, collision is possible, perhaps someone of Qliktech can clarify that

- if you want to store the primary key in qvd I think you should use hash (128 or 256) instead of autonumberhash