topic PROC SQL - DELETE FROM TABLE in SAS Programming

PROC SQL - DELETE FROM TABLE

tom12122 — Tue, 27 Mar 2012 16:24:26 GMT

When I use PROC SQL; DELETE FROM TABLE; i see that sas file is constantly increasing. How can I enforce (with some option perhaps) to delete recordes permanently and free the disk space?

PROC SQL - DELETE FROM TABLE

Haikuo — Tue, 27 Mar 2012 16:34:11 GMT

I am not sure if this is relevant: if I use system options compress=yes, and then after I delete some records, the file size remains the same, unless you invoke another system option: reuse=yes.

So it would look like this:

options compress=yes;

options reuse=yes;

What it does is to reuse those vacant slots from deleted records instead of appending to the end.

BTW, these two options are also data set options as well.

Regards,

Haikuo

PROC SQL - DELETE FROM TABLE

Ksharp — Wed, 28 Mar 2012 06:57:15 GMT

I don't understand what you mean.

If you want delete a table ,then use DROP TABLE

If you want keep the constructure of a table ,then use CREAT TABLE xx LIKE xx, then drop the original table.

Ksharp

PROC SQL - DELETE FROM TABLE

manojinpec — Wed, 28 Mar 2012 07:58:44 GMT

Example of your query and what you are trying to achieve? Please elaborate

PROC SQL - DELETE FROM TABLE

tom12122 — Wed, 28 Mar 2012 08:21:43 GMT

I've got table T1.

When I delete all record from it (Proc sql; Delete from T1;) the table size doesn't decrease. Moreover, when I put some records in this table I see that record number shows as If there were some "invisible records" inside. System seems to keep deleted record which take disk space and when iserting new records the table size is contantly growing..

PROC SQL - DELETE FROM TABLE

manojinpec — Wed, 28 Mar 2012 08:25:29 GMT

when you delete all records from table , try seeing contents of dataset and see if you can see that or not.

PROC SQL - DELETE FROM TABLE

Ksharp — Wed, 28 Mar 2012 08:58:59 GMT

Then you tried the way HaiKuo proposed?

PROC SQL - DELETE FROM TABLE

Tom — Wed, 28 Mar 2012 11:20:43 GMT

You seem to have figured out how SAS works when you delete records without recreating the dataset. If it is a concern to you then recreate the dataset. (data old; set old; run;)