June 19, 2013

Post: Analyzing Slow Query Table in MySQL 5.6

…and I wanted to check if any improvement has been made to the slow query log in table format.  Users … of script in the past, but here’s mine: cat <<'GO' | mysql --raw --skip-column-names –quick –…start_time), ‘;’, CHAR(10), IF(FIND_IN_SET(sql_text, ‘Sleep,Quit,Init DB,Query,Field List,Create DB…

Post: Debugging problems with row based replication

in particular that the server is trying to find is c1=1, but how can we findSQL statements.  I say semi-valid because the statements do not include column namesColumn names are not included in

Comment: Duplicate indexes and redundant indexes

in a foreign key constraint +++Query++++ SELECT a.table_schema, a.table_name, a.constraint_name, a.constraint_type, convert(group_concat(DISTINCT b.column_name

Post: High-Performance Click Analysis with MySQL

to handle this now. You can have the clicks column record the total, and the blue_clicks column record only blue clicks; to findto write a little more complex queries, but that’s often justified by a large reduction in table

Post: PROCEDURE ANALYSE

to find the optimal data type for the column value – for example columnin most cases ? These and similar tasks are often done by bunch of SQL queries while really MySQL has a native feature to

Post: A common problem when optimizing COUNT()

to MySQL. The problem is when the COUNT() contains a column name, like this: select count(col1) from table; If you know your SQLin your query. You meant to count the number of times the column‘s value is not null. This in… good place to learn about what it does. 90% of what you can find online is …

Comment: SQL Injection Questions Followup

to spot queries that are attempting to do SQL injection. The –review table contains a column named ‘reviewed’. You can use this table to mark all of your normal SQL query

Post: What exactly is read_rnd_buffer_size

in sorted order. If you use many queriestoSQL or storage engine. Honestly as it had name very similar to read_buffer_size which is currently only used by MyISAM tablesin following conditions): Row pointers are stored in the sort_buffer, not the whole data selected Blob/Text columns