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How to Optimize our QV application ?

Thanks

Helen

1 Solution

Accepted Solutions
er_mohit
Honored Contributor II

Re: How to Optimize our QV application ?

When you fetching data from data source and store it into qvd then again load that data from qvd and without filter it reload the qvd meaning optimizing

here look it

  1. 1)      Optimized and unoptimized QVD Load Situations?
  2. Ans. When concatenating two tables that don't have the same number of fields, if the second table has the same fields than the first one and then some extra fields the load will still be optimized, if done the other way around it will not be optimized.

e.g. All Loads are optimized

Table:

LOAD // Optimized

     A,

     B,

     C

FROM Table1.qvd (qvd);

CONCATENATE(Table) // Optimized

LOAD

     A,

     B,

     C,

     D,

     E

FROM Table2.qvd (qvd);

e.g. 2nd Load isn't optimized

Table:

LOAD // Optimized

     A,

     B,

     C,

     D,

     E

FROM Table2.qvd (qvd);

CONCATENATE(Table) // Not optimized

LOAD

     A,

     B,

     C

FROM Table1.qvd (qvd);

     Or   2nd Ans. Is

Optimized load is much faster and therefore preferable, especially for larger data sets.

Optimized loads are possible if no transformations (calculations) are made during the load, and no (almost) filtering is done in a WHERE clause.

The only acceptable filter is using function Exists:

WHERE Exists(Field)

So for example this load can't be optimized:

Load * From ... WHERE Country = 'US'

but this load can:

Load * From ... WHERE EXISTS(Country)

================================

On the other hand, the only time you want the load not to be optimized, is if you load a Mapping table from a QVD file. In this case, Optimized load doesn't quite work, so you want to make the load non-optimized deliberately.

Another Answer For Optimize and Non- Optimized

Optimized load is much faster and therefore preferable, especially for larger data sets.

Optimized loads are possible if no transformations (calculations) are made during the load, and no (almost) filtering is done in a WHERE clause.

The only acceptable filter is using function Exists:

WHERE Exists(Field)

So for example this load can't be optimized:

Load * From ... WHERE Country = 'US'

but this load can:

Load * From ... WHERE EXISTS(Country)

================================

On the other hand, the only time you want the load not to be optimized, is if you load a Mapping table from a QVD file. In this case, Optimized load doesn't quite work, so you want to make the load non-optimized deliberately.

3 Replies
Siva_Sankar
Honored Contributor

Re: How to Optimize our QV application ?

Helen,

Qlikview Optimization can be done at many levels. Find the attached document for brief explanation with examples.

Regards.

Sivasankar k

sujeetsingh
Honored Contributor III

Re: How to Optimize our QV application ?

Go this PDF i have placed at community

http://community.qlik.com/docs/DOC-4556

er_mohit
Honored Contributor II

Re: How to Optimize our QV application ?

When you fetching data from data source and store it into qvd then again load that data from qvd and without filter it reload the qvd meaning optimizing

here look it

  1. 1)      Optimized and unoptimized QVD Load Situations?
  2. Ans. When concatenating two tables that don't have the same number of fields, if the second table has the same fields than the first one and then some extra fields the load will still be optimized, if done the other way around it will not be optimized.

e.g. All Loads are optimized

Table:

LOAD // Optimized

     A,

     B,

     C

FROM Table1.qvd (qvd);

CONCATENATE(Table) // Optimized

LOAD

     A,

     B,

     C,

     D,

     E

FROM Table2.qvd (qvd);

e.g. 2nd Load isn't optimized

Table:

LOAD // Optimized

     A,

     B,

     C,

     D,

     E

FROM Table2.qvd (qvd);

CONCATENATE(Table) // Not optimized

LOAD

     A,

     B,

     C

FROM Table1.qvd (qvd);

     Or   2nd Ans. Is

Optimized load is much faster and therefore preferable, especially for larger data sets.

Optimized loads are possible if no transformations (calculations) are made during the load, and no (almost) filtering is done in a WHERE clause.

The only acceptable filter is using function Exists:

WHERE Exists(Field)

So for example this load can't be optimized:

Load * From ... WHERE Country = 'US'

but this load can:

Load * From ... WHERE EXISTS(Country)

================================

On the other hand, the only time you want the load not to be optimized, is if you load a Mapping table from a QVD file. In this case, Optimized load doesn't quite work, so you want to make the load non-optimized deliberately.

Another Answer For Optimize and Non- Optimized

Optimized load is much faster and therefore preferable, especially for larger data sets.

Optimized loads are possible if no transformations (calculations) are made during the load, and no (almost) filtering is done in a WHERE clause.

The only acceptable filter is using function Exists:

WHERE Exists(Field)

So for example this load can't be optimized:

Load * From ... WHERE Country = 'US'

but this load can:

Load * From ... WHERE EXISTS(Country)

================================

On the other hand, the only time you want the load not to be optimized, is if you load a Mapping table from a QVD file. In this case, Optimized load doesn't quite work, so you want to make the load non-optimized deliberately.

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