Allow background workers to connect to no particular database.

The documentation claims that this is supported, but it didn't
actually work.  Fix that.

Reported by Pavel Stehule; patch by me.

diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c
index 2fba6b772dced028362573a2f76d4125237b0ee3..0e7b5fad2dd1fa1ce7c050de76451ad6584a0f67 100644 (file)
--- a/src/backend/utils/init/postinit.c
+++ b/src/backend/utils/init/postinit.c
@@ -827,7 +827,7 @@ InitPostgres(const char *in_dbname, Oid dboid, const char *username,
        /* take database name from the caller, just for paranoia */
        strlcpy(dbname, in_dbname, sizeof(dbname));
    }
-   else
+   else if (OidIsValid(dboid))
    {
        /* caller specified database by OID */
        HeapTuple   tuple;
@@ -847,6 +847,18 @@ InitPostgres(const char *in_dbname, Oid dboid, const char *username,
        if (out_dbname)
            strcpy(out_dbname, dbname);
    }
+   else
+   {
+       /*
+        * If this is a background worker not bound to any particular
+        * database, we're done now.  Everything that follows only makes
+        * sense if we are bound to a specific database.  We do need to
+        * close the transaction we started before returning.
+        */
+       if (!bootstrap)
+           CommitTransactionCommand();
+       return;
+   }
 
    /*
     * Now, take a writer's lock on the database we are trying to connect to.