June 19, 2013

Post: Choosing a MySQL HA Solution - Post-Webinar Q&A

June 7, 2013 By Leave a Comment

… having issues receiving packets from the other side, things start…compared to 5.5, such as bug #69258, and bug #69318, and I think it might take one or two…-running queries in the output of SHOW PROCESSLIST that … RAC; all of the SQL nodes in a MySQL …tables and insert a few rows into an InnoDB table, …

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Post: Shard-Query EC2 images available

May 11, 2011 By 2 Comments

…row *************************** Name: ontime_fact Engine: InnoDB Version: 10 Row_format: Compact Rows: 6697533 Avg_row…compression ratio(compared to Innodb, 8:1 compared to … or two nodes. You should start two workers …sql. I have also provided a convenient script which will summarize the output from…

Filed Under: MySQL

Post: Flexviews - part 3 - improving query performance using materialized views

April 4, 2011 By 20 Comments

…from standard input, and outputs the SQL_API statements representing the original SQL statements. Each MV name will be taken from…

Filed Under: Insight for DBAs, MySQL

Post: A micro-benchmark of stored routines in MySQL

August 16, 2009 By 7 Comments

… sql_no_cache sum(ci.Population) from City as ci where CountryCode in ( select distinct co.Code from Country…it, we get output similar to the first table shown above, but the further two rows are not shown…. (If you think of a better way to compare apples and uhm, apples… please comment). The poorly…

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Post: A case for MariaDB's Hash Joins

May 31, 2012 By Leave a Comment

… ‘supplier’: 11M Table ‘orders’: 468M I have benchmarked two different kinds of workloads, IO bound and in-… is 1266x times when compared to MySQL 5.5 and 9x times when compared to MySQL 5.6. …1M rows) from one table with a large table The SQL used for this test together with its EXPLAIN output as …

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Post: Using Flexviews - part one, introduction to materialized views

March 23, 2011 By 3 Comments

…output of any SQL query is logically an in-memory table The output of a SQL…compared to computing the results. You can often generate multiple different blocks of content from… time.   There are two different methods by which a … rows must be examined The rows examined are related to the rows which …

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Post: SHOW INNODB STATUS walk through

July 17, 2006 By 40 Comments

…INNODB STATUS output, showing what you can learn from SHOW INNODB STATUS output and how… 3463, OS waits 3163 There are two portions in this section. One …rounds”. Spin locks are low cost wait, compared to OS wait, it is … localhost root Sending data select sql_calc_found_rows * from b limit 5 Trx read…

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Post: InnoDB Full-text Search in MySQL 5.6 (part 1)

February 26, 2013 By 1 Comment

…search, in the sense that the SQL required to run a MATCH .. AGAINST…the table, run an OPTIMIZE or two, delete some data, and see what … rows in set (0.00 sec) mysql> delete from dir_test_innodb LIMIT 200000; Query OK, 200000 rows…initial states, run some queries, and compare the output. Stay tuned, it…

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Post: How does MySQL Replication really work?

January 9, 2013 By 9 Comments

… events can be one of two types: Statement based – in which case these are write queries Row based – in this case these… you can compare it to the output of “show master status\G” from the master. 2. SQL thread The second process – SQL thread – reads events from a… that by comparing the replication status variables mentioned above to the master binary log status from the output of “show master status\G” from the…

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