-fix issue with multiple dbinit running concurrently

2 files changed, 7 insertions, 2 deletions

diff --git a/src/sync/sync-httpd_mhd.c b/src/sync/sync-httpd_mhd.c
index fa2344b..54b41f2 100644
--- a/src/sync/sync-httpd_mhd.c
+++ b/src/sync/sync-httpd_mhd.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2014, 2015, 2016 GNUnet e.V. and INRIA
+  Copyright (C) 2014, 2015, 2016 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Affero General Public License as published by the Free Software
diff --git a/src/syncdb/versioning.sql b/src/syncdb/versioning.sql
index 116f409..c7fa812 100644
--- a/src/syncdb/versioning.sql
+++ b/src/syncdb/versioning.sql
@@ -146,12 +146,17 @@
 
 BEGIN;
 
+-- Added by Christian Grothoff to support concurrency, see
+-- https://stackoverflow.com/questions/29900845/create-schema-if-not-exists-raises-duplicate-key-error?rq=4
+LOCK TABLE pg_catalog.pg_namespace;
+
+
 -- This file adds versioning support to database it will be loaded to.
 -- It requires that PL/pgSQL is already loaded - will raise exception otherwise.
 -- All versioning "stuff" (tables, functions) is in "_v" schema.
 
 -- All functions are defined as 'RETURNS SETOF INT4' to be able to make them to RETURN literally nothing (0 rows).
--- >> RETURNS VOID<< IS similar, but it still outputs "empty line" in psql when calling.
+-- >> RETURNS VOID<< IS similar, but it still outputs "empty line" in psql when calling
 CREATE SCHEMA IF NOT EXISTS _v;
 COMMENT ON SCHEMA _v IS 'Schema for versioning data and functionality.';