Consider 3.x upgrade-compatible with 2.x

Closes #4170

As I was at it, I also replaced the use of a temporary function
with a DO block.

git-svn-id: http://svn.osgeo.org/postgis/trunk@16713 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/utils/postgis_proc_upgrade.pl b/utils/postgis_proc_upgrade.pl
index a83af4282e2866adcce48ed3ec24e78846ab1630..148ec535f3824a1e623959b70d03e62ddd24369c 100755 (executable)
--- a/utils/postgis_proc_upgrade.pl
+++ b/utils/postgis_proc_upgrade.pl
@@ -467,9 +467,7 @@ print "DROP TABLE _postgis_upgrade_info;\n";
 
 __END__
 
-CREATE OR REPLACE FUNCTION postgis_major_version_check()
-RETURNS text
-AS '
+DO $$
 DECLARE
        old_scripts text;
        new_scripts text;
@@ -491,26 +489,26 @@ BEGIN
        BEGIN
                SELECT into old_scripts MODULE_lib_version();
        EXCEPTION WHEN OTHERS THEN
-               RAISE DEBUG ''Got %'', SQLERRM;
+               RAISE DEBUG 'Got %', SQLERRM;
                SELECT into old_scripts MODULE_scripts_installed();
        END;
-       SELECT into new_scripts ''NEWVERSION'';
+       SELECT into new_scripts 'NEWVERSION';
        SELECT into old_maj substring(old_scripts from 1 for 2);
        SELECT into new_maj substring(new_scripts from 1 for 2);
 
+       -- 2.x to 3.x was upgrade-compatible, see
+       -- https://trac.osgeo.org/postgis/ticket/4170#comment:1
+       IF new_maj = '3' AND old_maj = '2' THEN
+               old_maj = '3'; -- let's pretend old major = new major
+       END IF;
+
        IF old_maj != new_maj THEN
-               RAISE EXCEPTION ''Upgrade of MODULE from version % to version % requires a dump/reload. See PostGIS manual for instructions'', old_scripts, new_scripts;
-       ELSE
-               RETURN ''Scripts versions checked for upgrade: ok'';
+               RAISE EXCEPTION 'Upgrade of MODULE from version % to version % requires a dump/reload. See PostGIS manual for instructions', old_scripts, new_scripts;
        END IF;
 END
-'
+$$
 LANGUAGE 'plpgsql';
 
-SELECT postgis_major_version_check();
-
-DROP FUNCTION postgis_major_version_check();
-
 CREATE TEMPORARY TABLE _postgis_upgrade_info AS WITH versions AS (
   SELECT 'NEWVERSION'::text as upgraded,
   MODULE_scripts_installed() as installed