Remove xid_to_int4 postgres function

[rails.git] / db / functions / functions.sql

diff --git a/db/functions/functions.sql b/db/functions/functions.sql
index 5e3d4bcb3cc869522a719382d184743af8384a82..97e44f0cec1bf5a82f3101329429f8ae110dddee 100644 (file)
--- a/db/functions/functions.sql
+++ b/db/functions/functions.sql
@@ -40,34 +40,3 @@ BEGIN
   RETURN (x << 1) | y;
 END;
 $$ LANGUAGE plpgsql IMMUTABLE;
-
-
--- xid_to_int4 converts a PostgreSQL transaction ID (xid) to a 32-bit integer
--- which can then be used to efficiently find rows which have changed between
--- two given transactions. This is currently used by Osmosis to extract a
--- stream of edits for "diff replication" **HOWEVER** this is a pain point, as
--- (ab)using the xid in this way is _not_ supported or recommended by Postgres
--- devs. It is preventing us upgrading to PostgreSQL version 10+, and will
--- hopefully be replaced Real Soon Now.
---
--- From the Osmosis distribution by Brett Henderson:
--- https://github.com/openstreetmap/osmosis/blob/master/package/script/contrib/apidb_0.6_osmosis_xid_indexing.sql
-CREATE OR REPLACE FUNCTION xid_to_int4(t xid)
-  RETURNS integer
-  AS
-$$
-DECLARE
-  tl bigint;
-  ti int;
-BEGIN
-  tl := t;
-
-  IF tl >= 2147483648 THEN
-    tl := tl - 4294967296;
-  END IF;
-
-  ti := tl;
-
-  RETURN ti;
-END;
-$$ LANGUAGE 'plpgsql' IMMUTABLE STRICT;