… out to get to the bottom of the matter. First, I stopped the…type: Query Server_id: 1 End_log_pos: 176 Info: drop temporary table test.t *************************** 6. row *************************** …bin.000006 Slave_IO_Running: No Slave_SQL_Running: No …… omitted ……… slave1 > start slave…
Post: Can MySQL temporary tables be made safe for statement-based replication?
May 26, 2008 By 8 Comments
Post: Analyzing Slow Query Table in MySQL 5.6
February 18, 2013 By 1 Comment
…id=”attachment_12961″ align=”alignright” width=”300″] Analyzing SQL Queries…SQL Queries with Percona Toolkit. This is a guided tour of best practices for pt-query…of the query log table into a flat file in the format of a conventional query…
Post: EXPLAIN EXTENDED can tell you all kinds of interesting things
June 15, 2010 By 7 Comments
…query before it actually executes it. This process is called query rewriting, and it is a part of any good SQL…of ‘const’ table which is used when a table contains only one row. The contents of these tables are read before the query begins executing. Because of…
Post: A micro-benchmark of stored routines in MySQL
August 16, 2009 By 7 Comments
… compare the speed of a stored function against …and cooked up this query: select sql_no_cache …table scan against the first query, and then executing the subquery for each row: mysql> explain select ….\G *************************** 1. row *************************** id: 1 select_type: PRIMARY table…
Post: The new cool MySQL patch has landed! Check your queries performance!
October 31, 2007 By 16 Comments
…Rows_examined: 1113 LOGGING OF THE REPLICATED STATEMENTS Normally MySQL will not write into slow log any queries executed by the slave’s SQL…rows from a table. Full_join means any of the joins didn’t use indexes. If a temporary table is required for query execution Tmp_table…
Post: MySQL Query Cache
July 27, 2006 By 70 Comments
…of usable memory – Queries are constantly being invalidated from query cache by table updates, this means number of queries…SQL_CACHE hint for queries which you want to have cached – such as SELECT SQL_CACHE col from foo where id…
Post: Slow DROP TABLE
June 16, 2009 By 21 Comments
…Query | 7 | NULL | drop table large_table | | 329 | root | localhost | test | Query | 7 | Opening tables | select sql_no_cache * from other_table…table large_table; Query OK, 0 rows affected (7.44 sec) XFS mysql> drop table large_table; Query OK, 0 rows…
Post: Eventual Consistency in MySQL
November 18, 2011 By 8 Comments
…row in set (0.00 sec) It can be a dizzying exercise to write SQL queries that in turn output valid SQL queries…table with similar structure, and track our database design manually, so we can use the same SQL queries for quality control: mysql> CREATE TABLE…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
… 442 mysql tables in use 1, locked 0 MySQL thread id 8079, query id 728899 localhost root Sending data select sql_calc_found_rows * from b… of tables locked by transactions. Innodb does not lock tables for normal operation so number of tables locked normally stays 0, unless it is ALTER TABLE…
Post: Shard-Query EC2 images available
May 11, 2011 By 2 Comments
…row store for queries which access a significant amount of…sql-mode=STRICT_TRANS_TABLES symbolic-links table-definition-cache=16384 table-open-cache=128 thread-cache-size=32 thread-stack=256K tmp-table…
