Commit 0f5d7bcb authored by heikki@donna.mysql.fi's avatar heikki@donna.mysql.fi
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manual.texi: 

  Added foreign key def syntax + note that the check is not deferred to trx commit
parent 7f5f58dc

Docs/manual.texi

+8 −0
Original line number Diff line number Diff line
@@ -35283,6 +35283,12 @@ your job again, rather than wait for millions of disk i/os to complete. 
InnoDB version 3.23.44 features foreign key constraints. InnoDB is the

first MySQL table type which allows you to define foreign key

constraints to guard the integrity of your data.













The syntax of a foreign key constraint definition in InnoDB:













@example













FOREIGN KEY (index_col_name, ...) REFERENCES table_name (index_col_name, ...)













@end example



























An example:





























@example









@@ -35303,6 +35309,8 @@ The size and the signedness of integer types has to be same.



























When doing foreign key checks InnoDB sets shared row















level locks on child or parent records it has to look at.













InnoDB checks foreign key constraints immediately: the check













is not deferred to transaction commit.





























InnoDB allows you to drop any table even though that















would break the foreign key constraints which reference