topic Re: I can not set numeric length on LASR data set. in SAS Visual Analytics

I can not set numeric length on LASR data set.

LDYL — Tue, 03 Oct 2017 12:15:58 GMT

I am currently struggling with a space optimisation problem. I can not compress data, because a star schema will be applied on them, so that I am trying to reduce the size "manually". I figured out that a lot of space is lost by storing small numbers on 8 bytes.

However I can not reduce the length of a numeric variable stored on LASR server. For example: even when I upload a table with numeric variables lengths set to 3. all lengths are automatically set to 8. on the server.

How can I determine this length? Is that a server configuration issue?

Any help will be appreciated.

Re: I can not set numeric length on LASR data set.

alexal — Tue, 03 Oct 2017 12:35:57 GMT

@LDYL,

Each column in the LASR server is padded to an 8-byte boundary. If the variable you are adding is not a multiple of 8 bytes, the variable will be padded to an 8-byte boundary.

Read this: https://en.wikipedia.org/wiki/Data_structure_alignment

Re: I can not set numeric length on LASR data set.

LDYL — Tue, 03 Oct 2017 12:49:27 GMT

Thank You @alexal

could You recommend me any possible solution how to reduce the size of dataset on LASR,

however with the star schema being applied ?

Can I somehow combine compression with star schema?

Re: I can not set numeric length on LASR data set.

alexal — Tue, 03 Oct 2017 14:42:37 GMT

@LDYL,

how to reduce the size of dataset on LASR, however with the star schema being applied ?

There is no way.

Can I somehow combine compression with star schema?

No.

Re: I can not set numeric length on LASR data set.

SASKiwi — Tue, 03 Oct 2017 19:30:26 GMT

One strategy I've successfully used to reduce space is to make use of codes in character variables which are expanded to full descriptions using SAS formats (eg store USA in a character variable and have a SAS format which applies United States of America).

Also if you want to compress numeric variables that are just codes that aren't used in calculations, convert them to character.

Please note that even when you are able to compress LASR tables, in my experience the performance degradation is significant.