Pg and Ora still have differences in the application of large data table ah, how

4 millions of lines of the record, add index, count (*), AVG operation, Oracle completed in 20 seconds,
The same operation PG environment also sent a large margin ah, change of share, memory are not used, what a good way to optimize.?

Started by Edwin at March 05, 2016 - 5:02 AM

The columns of the table number and type? How much data is, in addition to increase work_mem.

Posted by Jocelyn at March 17, 2016 - 5:59 AM

With ORACLE of memory areas to open as large, increase working memory area and sort area parameters, try.

Should not be bad lot,

Posted by Lyndon at March 23, 2016 - 6:43 AM

4 millions of rows of data increases, the work_mem effect is significant, AVG is 10 seconds, Oracle is 2 seconds, but compared with the previous, performance can be accepted！

Posted by Edwin at April 06, 2016 - 6:52 AM

Oracle is indexing

PG is not indexed, to a full table scan.

Gap here.

Unconditional count (*) is a PG is not indexed

Posted by Duncan at April 15, 2016 - 7:11 AM