Hello Do you want to search for tables with many unordered rows? SELECT schemaname, tablename, correlation FROM pg_stats WHERE abs(correlation) < 0.2 and schemaname not in ('pg_catalog', 'information_schema') ; Or do you want to put the table in order? BEGIN; CREATE TABLE tbl_test_new (LIKE tbl_test INCLUDING ALL); INSERT INTO tbl_test_new SELECT * FROM tbl_test ORDER BY id; DROP TABLE tbl_test; TABLE tbl_test_new RENAME TO tbl_test; COMMIT; If you really want to get a correlation of near 0 try INSERT INTO tbl_test (name) SELECT random() FROM generate_series(1, 100); bye, -christian- Am Mon, 26 Nov 2012 01:52:21 -0800 (PST) schrieb classical_89 <luongnx512@xxxxxxxxx>: > Hi,First sorry for my bad English :D.I'm new in PostgreSQL and > database .Now i'm researching about statistic correlation .I want to > make a example with the table -assume that I have tbl_test table and > two column - id & name - and do something to get correlation of a > column is near 0 (zero).What step can i do ? > Thanks for your support :) > > > > -- > View this message in context: > http://postgresql.1045698.n5.nabble.com/Correlation-in-pg-stats-tp5733524.html > Sent from the PostgreSQL - general mailing list archive at Nabble.com. > > -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general