Fix SQL queue manager so it actually stores and executes the pre and post…

Fix SQL queue manager so it actually stores and executes the pre and post transaction SQL statements.

src/switch_core_sqldb.c

@@ -1514,10 +1514,16 @@ SWITCH_DECLARE(switch_status_t) switch_sql_queue_manager_init_name(const char *n
 	}
 
 	if (pre_trans_execute) {
-		qm->pre_trans_execute = switch_core_strdup(qm->pool, qm->pre_trans_execute);
-		qm->post_trans_execute = switch_core_strdup(qm->pool, qm->post_trans_execute);
-		qm->inner_pre_trans_execute = switch_core_strdup(qm->pool, qm->inner_pre_trans_execute);
-		qm->inner_post_trans_execute = switch_core_strdup(qm->pool, qm->inner_post_trans_execute);
+		qm->pre_trans_execute = switch_core_strdup(qm->pool, pre_trans_execute);
+	}
+	if (post_trans_execute) {
+		qm->post_trans_execute = switch_core_strdup(qm->pool, post_trans_execute);
+	}
+	if (inner_pre_trans_execute) {
+		qm->inner_pre_trans_execute = switch_core_strdup(qm->pool, inner_pre_trans_execute);
+	}
+	if (inner_post_trans_execute) {
+		qm->inner_post_trans_execute = switch_core_strdup(qm->pool, inner_post_trans_execute);
 	}
 
 	*qmp = qm;