diff --git a/hshetl/jobs.py b/hshetl/jobs.py
index 90cd68a4c84db063f490197a9fdb43b75b71fdcf..4e3c0bac35237816ca7d62481555e5434389b6e9 100644
--- a/hshetl/jobs.py
+++ b/hshetl/jobs.py
@@ -349,9 +349,9 @@ class PlSqlQueryJob(QueryJob):
     '''The default description of this job.'''
 
     def __init__(self, connector, *args, **kwargs):
-        if not isinstance(connector, SqlQueryLanguageSupportMixin):
-            raise ConfigurationException('plsqlquery can only be executed on oracle or postgresql connections.')
         super(PlSqlQueryJob, self).__init__(connector = connector, *args, **kwargs)
+        if not isinstance(self.connector, SqlQueryLanguageSupportMixin):
+            raise ConfigurationException('plsqlquery can only be executed on oracle or postgresql connections.')
 
     def _execute(self):
         self.connector.execute_plsql(self.sql)