-fix aggregator with deferred constraint

1 files changed, 16 insertions, 1 deletions

diff --git a/src/exchangedb/plugin_exchangedb_postgres.c b/src/exchangedb/plugin_exchangedb_postgres.c
index c80f33707..507a2c66c 100644
--- a/src/exchangedb/plugin_exchangedb_postgres.c
+++ b/src/exchangedb/plugin_exchangedb_postgres.c
@@ -7949,7 +7949,22 @@ postgres_start_deferred_wire_out (void *cls)
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_ExecuteStatement es[] = {
     GNUNET_PQ_make_execute ("START TRANSACTION ISOLATION LEVEL READ COMMITTED"),
-    GNUNET_PQ_make_try_execute ("SET CONSTRAINTS wire_out_ref DEFERRED"),
+    GNUNET_PQ_make_execute ("DO $$"
+                            "BEGIN"
+                            " IF EXISTS ("
+                            "   SELECT 1"
+                            "     FROM information_Schema.constraint_column_usage"
+                            "    WHERE table_name='wire_out'"
+                            "      AND constraint_name='wire_out_ref')"
+                            "  THEN "
+                            "  SET CONSTRAINTS wire_out_ref DEFERRED;"
+                            "  END IF;"
+                            "END $$"),
+    // FIXME: above logic is better as it tests that the constraint
+    // is actually applicable; but maybe we want to drop the constraint
+    // entirely once do_gc() is fixed to do without it?
+    //    GNUNET_PQ_make_execute ("CALL defer_wire_out()"),
+    //    GNUNET_PQ_make_execute ("SET CONSTRAINTS wire_out_ref DEFERRED;"),
     GNUNET_PQ_EXECUTE_STATEMENT_END
   };