Improving constraint handling for Oracle databases: disable only constraints that reference the tables that I update. Ensure that this works even if the current user doesn't own the tables that I will update by looking at ALL_* views and applying the schema name.
Merge pull request #51 from mdahm/master

pktable may have been filtered, too
Merge pull request #47 from ahus1/_ahus1_fix_oracleconstraints

Improving constraint handling for Oracle databases
slightly modified