…how SchemaSpy identifies the relationship, and whether you need to provide a hint or not. Running SchemaSpy (with Foreign Keys…to write the output to, make…to use the search feature of your browser to zero in on a particular table Constraints – lists the explicit Foreign Key constraints in…
Post: Hijacking Innodb Foreign Keys
January 2, 2012 By 2 Comments
…in many cases and foreign keys are still handled on storage engine level making them not working for partitioned tables as well as making foreign keys…
Post: Logging Foreign Key errors
September 27, 2012 By Leave a Comment
…how to log deadlock errors using Percona Toolkit. Foreign key errors have the same problems. InnoDB only logs the last error in…in the foreign key in table is “PRIMARY” See http://dev.mysql.com/doc/refman/5.5/en/innodb-foreign-key-constraints.html for correct foreign key…
Post: Instrumentation and the cost of Foreign Keys
September 20, 2010 By 9 Comments
… whether or not to use Foreign Key constraints on InnoDB tables. My standard response has always been: “it depends on how much of a tradeoff you are willing to make for performance. In some situations the cost can be… without the foreign key constraints does not block on the last statement. We also see the expected output change to: mysql> SELECT * FROM…
Post: Percona Server on the Raspberry Pi: Your own MySQL Database Server for Under $80
February 25, 2013 By 10 Comments
…to write the image to. Make sure you selected the right drive and click “Install”. The image gets written to…foreign keys | YES | YES | YES | [...] mysql> SELECT “Hello World!” AS “Success!” \G *************************** 1. row *************************** Success!: Hello World! 1 row in…
Post: Joining many tables in MySQL - optimizer_search_depth
April 20, 2012 By 8 Comments
…foreign keys just in case) which would take 5 seconds even though in the read less than 1000 rows and doing it completely in…in join I think faster execution plan computation would be more important than backward compatibility. In MySQL 5.6 things are likely to…
Post: How to load large files safely into InnoDB with LOAD DATA INFILE
July 3, 2008 By 29 Comments
…, the purge thread will have to clean these up. This is how you make InnoDB behave like PostgreSQL 
If…rows were small). But how to do this without splitting the file? The answer lies in the Unix fifo….of loading the entire 4GB file in one chunk: time mysql -e “set foreign_key_checks=0; set sql_log…
Post: MySQL Error Message Nonsenses
March 16, 2008 By 7 Comments
…one. How do you expect to decode from this message this means storage engine in …MySQL error code 150: Foreign key constraint is incorrectly formed What is also interesting is – this error 150 is in… pluggable storage engine interface Sun/MySQL spends some time to make things consistent. There should…
Post: Best kept MySQLDump Secret
March 23, 2012 By 13 Comments
…how MySQL‘s Transactions work with DDL, In particular ALTER TABLE. When ALTER TABLE is Performed in…KEYS */; UNLOCK TABLES; /*!40103 SET TIME_ZONE=@OLD_TIME_ZONE */; /*!40101 SET SQL_MODE=@OLD_SQL_MODE */; /*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY…
Post: InnoDB's gap locks
March 27, 2012 By 15 Comments
…to other sessions. How to troubleshoot gap locks? Is possible to…to create locks to prevent that from happening. 2- innodb_locks_unsafe_for_binlog = 1. Disables the gap locks except for foreign-key…In the following link there is a good source of information: http://dev.mysql…
