RE: drop partitions

2012-05-14 Thread Rick James
Note that in many (too many) cases, _all_ partitions are opened, even if only one is really needed. > -Original Message- > From: louis liu [mailto:yloui...@gmail.com] > Sent: Monday, May 14, 2012 7:02 AM > To: Johan De Meersman > Cc: mysql@lists.mysql.com; Rick James >

Re: drop partitions

2012-05-14 Thread louis liu
not actually , first partition to have been dropped is no longer in use ,we dropped partition from old -> new 2012/5/14 Johan De Meersman > - Original Message - > > From: "Rick James" > > > > If you have 14 partitions in each of 390 tables, and if you have most > > of the tables '

Re: drop partitions

2012-05-14 Thread Johan De Meersman
- Original Message - > From: "Rick James" > > If you have 14 partitions in each of 390 tables, and if you have most > of the tables 'active', then you are possibly thrashing in the > table_open_cache. A distinct possibility. > Compute (SHOW STATUS): > Opened_tables / Uptime -- don't wan

RE: drop partitions

2012-05-11 Thread Rick James
ble_definitions / Uptime -- ditto > -Original Message- > From: louis liu [mailto:yloui...@gmail.com] > Sent: Friday, May 11, 2012 1:35 AM > To: mysql@lists.mysql.com > Subject: drop partitions > > Hi all > > last night we droped some partitions and we found tha

Re: drop partitions

2012-05-11 Thread louis liu
pen_cache > table_definition_cache > How partitions in this table? How many tables in your system? > > > -Original Message- > > From: louis liu [mailto:yloui...@gmail.com] > > Sent: Friday, May 11, 2012 1:35 AM > > To: mysql@lists.mysql.com > > Subject: drop part

RE: drop partitions

2012-05-11 Thread Rick James
t; To: mysql@lists.mysql.com > Subject: drop partitions > > Hi all > > last night we droped some partitions and we found that the first > drop costs about 30mins and then it's about 3 seconds. > > when droping the partition all processes a

drop partitions

2012-05-11 Thread louis liu
48650 | backend_log | Query | 1420 | Opening tables | insert into BACK_SQL_OPERATION_LOG (SUB_SYSTEM,OPERATION_TYPE,OP_CONDITION,OPERATION_TIME,OPERATION_ | whole instance hangs and all databases are waiting until we completely drop partitions

Re: 5.1.24-rc and partitioning and add, drop partitions and select

2008-05-12 Thread Krishna Chandra Prajapati
Hi, Alter table works on the whole table and it apply on whole table, irrespective of partition. It will block all other queries ( select, insert, update) until alter gets completed. On Mon, May 12, 2008 at 8:45 PM, Mariella Petrini <[EMAIL PROTECTED]> wrote: > > > One more question, plz > > (h

Re: 5.1.24-rc and partitioning and add, drop partitions and select

2008-05-12 Thread Mariella Petrini
One more question, plz (http://dev.mysql.com/doc/refman/5.1/en/partitioning-limitations.html) Table locks. The process executing a partitioning operation on a table takes a write lock on the table. Reads from such tables are relatively unaffected; pending INSERT and UPDATE operations are perf

5.1.24-rc and partitioning and add, drop partitions and select

2008-05-12 Thread Mariella Petrini
Hi ALL, I have been using 5.1.24-rc and partitioning by range. I have noticed that while doing a set of SELECT statements on one of the partitions (e.g. p1) and at the same time doing an ALTER TABLE with drop or add a different partition (e.g. ALTER TABLE DROP or ADD PARTITION p10) all the sele