Schema generation creates redundant indexes when using the Mysql5InnodbDialect ------------------------------------------------------------------------------ Key: HHH-3597 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-3597 Project: Hibernate Core Issue Type: Bug Components: core Environment: MySQL and any version of Hibernate with the Mysql5InnodbDialect (I checked trunk, the issue is still there) Reporter: Mark Matthews Priority: Critical Mysql5InnodbDialect incorrectly adds indexes when adding foreign key constraints. Since MySQL-4.1.2, Innodb has automatically added an index if needed, or re-uses one if it can when adding a foreign key constraint. Adding it by "hand" creates a duplicate index, which wastes resources (i/o, cpu, disk space). Reworking the following method fixes the issue: @Override public String getAddForeignKeyConstraintString( String constraintName, String[] foreignKey, String referencedTable, String[] primaryKey, boolean referencesPrimaryKey) { String cols = StringHelper.join(", ", foreignKey); return new StringBuffer(30) .append(" add constraint ") .append(constraintName) .append(" foreign key (") .append(cols) .append(") references ") .append(referencedTable) .append(" (") .append( StringHelper.join(", ", primaryKey) ) .append(')') .toString(); } -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://opensource.atlassian.com/projects/hibernate/secure/Administrators.... - For more information on JIRA, see: http://www.atlassian.com/software/jira