Percona's MySQL & InnoDB performance and scalability blog
…in a database and generates a visual representation of it in a browser-displayable format. It lets you click through the hierarchy of database tables…Tables – Names, number of children, parents, count of columns, row counts, and comments — a great way for a high level overview of the table…
…in a file name. Back in 1979, Monty developed an in-house database…sql.=”`$n`”; $sql.=” ENUM(‘”.cname(0,64).”‘) COMMENT ‘”.cname($_,254).”‘,\n”; } chop $sql; chop $sql; $sql.=”);”; print $sql; So the maximum number of columns for a table in…
…in our database…table by querying the various I_S.INNODB_FT_* tables. In particular, the INNODB_FT_CONFIG table…
…database-agnostic, not related to MySQL. The problem is when the COUNT() contains a column name, like this: select count(col1) from table; If you know your SQL well, you know COUNT() has two meanings. 1) count the number of rows 2) count…
…digest, the best tool for evaluating where your database response time is being spent. This month we… I read the logging code in MySQL 5.6.10 source, in file sql/log.cc. I discovered …tables are rounded down to the nearest whole second, meaning any query that executes in less than 1.0 seconds counts…
… tables in MyISAM format in “mysql” database. Plus HEAP/MEMORY tables are used for temporary tables…large pages in general. Currently MyISAM and Innodb. Some SQL level items…table locks or if LOCK TABLES are used. So in practice this option is used for MyISAM and MEMORY tables. max_write_lock_count…
…table. But just as frequently, I want to look up blog posts on variables, or look for content in…
… reflect the changes that have happened in the database, instead of replaying binary logs directly… the command line: $ cat sales.sql create table dashboard_customer_sales AS select customer_id,… in the order_lines table, three orders of magnitude more quickly than COUNT(*). mysql> select count(*) …
…in the dimension tables. It will be very interesting to test these queries on various engines and databases…
… sections in Semaphores information: ———- SEMAPHORES ———- OS WAIT ARRAY INFO: reservation count 13569, signal count 11421…tables in use 1, locked 0 MySQL thread id 8079, query id 728899 localhost root Sending data select sql… free pages is zero as in this case database pages will not be …
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