#2365: Significantly improve performance of find_srid when lots of geometry columns

git-svn-id: http://svn.osgeo.org/postgis/trunk@13461 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/postgis/postgis.sql.in b/postgis/postgis.sql.in
index ee791ef480167f849421a2021c93ba36dadbc6a4..aee062c34d1536e7d72ff451497e235c96fb092d 100644 (file)
--- a/postgis/postgis.sql.in
+++ b/postgis/postgis.sql.in
@@ -2565,35 +2565,23 @@ LANGUAGE 'plpgsql' VOLATILE STRICT;
 -----------------------------------------------------------------------
 -- FIND_SRID( <schema>, <table>, <geom col> )
 -----------------------------------------------------------------------
+-- Changed: 2.1.8 improve performance
 CREATE OR REPLACE FUNCTION find_srid(varchar,varchar,varchar) RETURNS int4 AS
 $$
 DECLARE
-       schem text;
-       tabl text;
+       schem varchar =  $1;
+       tabl varchar = $2;
        sr int4;
 BEGIN
-       IF $1 IS NULL THEN
-         RAISE EXCEPTION 'find_srid() - schema is NULL!';
-       END IF;
-       IF $2 IS NULL THEN
-         RAISE EXCEPTION 'find_srid() - table name is NULL!';
-       END IF;
-       IF $3 IS NULL THEN
-         RAISE EXCEPTION 'find_srid() - column name is NULL!';
-       END IF;
-       schem = $1;
-       tabl = $2;
 -- if the table contains a . and the schema is empty
 -- split the table into a schema and a table
 -- otherwise drop through to default behavior
-       IF ( schem = '' and tabl LIKE '%.%' ) THEN
+       IF ( schem = '' and strpos(tabl,'.') > 0 ) THEN
         schem = substr(tabl,1,strpos(tabl,'.')-1);
         tabl = substr(tabl,length(schem)+2);
-       ELSE
-        schem = schem || '%';
        END IF;
 
-       select SRID into sr from geometry_columns where f_table_schema like schem and f_table_name = tabl and f_geometry_column = $3;
+       select SRID into sr from geometry_columns where (f_table_schema = schem or schem = '') and f_table_name = tabl and f_geometry_column = $3;
        IF NOT FOUND THEN
           RAISE EXCEPTION 'find_srid() - couldnt find the corresponding SRID - is the geometry registered in the GEOMETRY_COLUMNS table?  Is there an uppercase/lowercase missmatch?';
        END IF;