4 messages in com.mysql.lists.mysqlRe: Help!! Big bad join!| From | Sent On | Attachments |
|---|---|---|
| volche | 08 Feb 2000 12:37 | |
| Tonu Samuel | 08 Feb 2000 13:23 | |
| volche | 09 Feb 2000 07:08 | |
| jcole | 09 Feb 2000 07:43 |
| Subject: | Re: Help!! Big bad join! |
|---|---|
| From: | Tonu Samuel (to...@mysql.com) |
| Date: | 02/08/2000 01:23:49 PM |
| List: | com.mysql.lists.mysql |
volche wrote:
500 tables (key(8byte), 20 columns (3byte)), 750 rows. Simple join: "select tbl1.key, tbl1.col, tbl2.col, .....tblN.col from tbl1, tbl2, ...,tblN where tbl1.key=tbl2.key= ...=tblN.key and tbl1.key between val1 and val2" Results: N=2 <1sec N=3 ~1sec N=4 13.5min!!!! And who needs join after this? What's going on here?
Post result of EXPLAIN command, db structure and mysqlbug output there. Then we maybe can answer your question.
-- +----------------------------------------------------------------+ | TcX ____ __ _____ _____ ___ | | /*/\*\/\*\ /*/ \*\ /*/ \*\ |*| Tõnu Samuel | | /*/ /*/ /*/ \*\_ |*| |*||*| to...@mysql.com | | /*/ /*/ /*/\*\/*/ \*\|*| |*||*| Tallinn, Estonia | | /*/ /*/ /*/\*\_/*/ \*\_/*/ |*|____ | | ^^^^^^^^^^^^/*/^^^^^^^^^^^\*\^^^^^^^^^^^ | | /*/ \*\ Developers Team | +----------------------------------------------------------------+