topic Re: index in QlikView

index

Fri, 08 May 2015 05:39:33 GMT

Hello Viewers,

I heard somewhere that creating indexes may increase the performance of the QVD.

what exactly Index does and how to create?

Plz help me out in this with perfect example.

Thanks in adv!!!

Re: index

anbu1984 — Fri, 08 May 2015 08:17:31 GMT

Index is available in Database not in Qlikview.

A database index supports fast data access in a very similar way to a book index or a printed phone book

Re: index

Fri, 08 May 2015 10:26:01 GMT

Thanks for suggestion

So then how we can creating indexes for the QVD performance???

Could you elaborate little bit more.

am still confusing on this that where it can be used and relation between index and QVD???

Plz could some one help me out in this.

Thanks in adv!!!

Re: index

petter — Fri, 08 May 2015 11:56:14 GMT

In QlikView you cannot create, update or delete any type of indexes. This is a fact and no suggestion. QlikView will perform at top speed because it handles "indexes" completely automated under the hood.

In effect all fields and all values - both text and numbers are indexed and deduplicated through its symbol table generation. That is why QlikView is so extremely fast in most situations...

Re: index

dgreenberg — Fri, 08 May 2015 21:16:30 GMT

The full context of what you heard is likely that creating indexes on your SQL tables will improve the performance of loading data into Qlikview. Qlikview is very efficient but a database without indexes is very inefficient.

Without indexes on tables you would perform constant full table scans.

I am not sure how that would affect performance in Qlikview if you were doing something simple like Load * from table1 but if you put any type of where clause on it the performance would suffer terribly.

It's poor design not to have a primary key or clustered index on a SQL table and those tables without clustered indexes are called heaps. Without indexes there is no way for you to search directly for John Smith, it must go down every single row looking for John Smith.

Hopefully you have a DBA who ensures the database servers are properly configured and maintained.