…: 17217646764 Index_length: 11993816064 mysql> show table status like ‘dim1′\G ***************************…Using where; Using temporary; Using filesort *************************** 2. row *************************** table: fact type: ref key_len: 4 rows: 606 Extra: Using where …
Post: The MySQL optimizer, the OS cache, and sequential versus random I/O
April 28, 2008 By 17 Comments
Post: Updated msl (microslow) patch, installation walk-through!
April 20, 2008 By 17 Comments
…. Please do not use the below example as it may not be suitable for your environment. (garfield:~/work/mysql-5.0.51a… to have the patched MySQL installed in the system. Locate where the original mysqld binary is with: (garfield:~/work/mysql-5.0.51a… to get only those which use on-disk temporary storage for intermediate results “tmp_table_on_disk,filesort_on_disk†would be…
Post: GROUP_CONCAT useful GROUP BY extension
September 4, 2006 By 49 Comments
… non-NULL values from a group. Where it can be useful? For example to get PHP … from PHP to MySQL server side. Also it can be handy to use result concatenated string… with joins, but sometimes we need the temporary ids in clients code, for example to… GROUP_BY to avoid unnecessary sorting with filesort…
