http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=8915 Priority: P5 - low Change sponsored?: --- Bug ID: 8915 Assignee: gmcharlt@gmail.com Summary: Referential integrity constraints and InnoDB vs MyISAM storage engine Severity: enhancement Classification: Unclassified OS: All Reporter: frederic@tamil.fr Hardware: All Status: NEW Version: rel_3_10 Component: Architecture, internals, and plumbing Product: Koha An increasing number of Koha functionalities rely on database level referential integrity constraints. For example, see bug 1963, when a biblio record is deleted, it is also deleted in all the virtual shelves containing it. If you do: SHOW CREATE TABLE virtualshelfcontents you see this specific constraint: CONSTRAINT shelfcontents_ibfk_2 FOREIGN KEY biblionumber REFERENCES biblio (biblionumber) ON DELETE CASCADE ON UPDATE CASCADE, Depending on MySQL storage engine, constraints are supported or not. InnoDB support referential integrity constraints, MyISAM doesn't. Since version 5.1, MySQL default storage engine is InnoDB. Prior to this version, MyISAM was the default engine. So depending on various parameters, a Koha DB can contain MyISAM tables, therefore without integrity constraints, when those constraints are required by Koha for proper operations. Those parameters are: - Old Koha DB can have been created at first place with MyISAM engine, and never upgraded to InnoDB. - The upgrade to InnoDB can have been done later, but some constraints have been added by updatedatabase.pl when tables was still MyISAM. - The InnoDB can be silently disabled on the server: DBA choice, bad my.cnf configuration, etc. -- You are receiving this mail because: You are watching all bug changes.