The temporary table created in eZContentObjectTreeNode::createPermissionCheckingSQL() has not indexes in eZ Publish 4.2.

If the changes introduced to this table, in eZ Publish 4.3, were backported to 4.2, this performance constraint would be solved.

Steps to reproduce

• Login, as a regular member, to a site with many members. Browse through the site and monitor the time consumed to generate the temporary table ezgroup_perm_tmp_%
• Create a few more users into the same group
• Review the time consumed to generate the table
• It should take longer and consume more space in temp