CartoDB-SQL-API/test/support/CDB_QueryTables.sql
Raul Ochoa ac0826dc91 Updates CDB_QueryTables to match the one from the extension. Fixes some tests to show the schema presence.
Skip some tests that we need to review because with the current implementation of CDB_QueryTables dont make sense.
CDB_QueryTables should be used from the extension as a dependency.
2014-06-26 11:22:40 +02:00

68 lines
1.8 KiB
PL/PgSQL

-- Return an array of table names scanned by a given query
--
-- Requires PostgreSQL 9.x+
--
CREATE OR REPLACE FUNCTION CDB_QueryTables(query text)
RETURNS name[]
AS $$
DECLARE
exp XML;
tables NAME[];
rec RECORD;
rec2 RECORD;
BEGIN
tables := '{}';
FOR rec IN SELECT CDB_QueryStatements(query) q LOOP
IF NOT ( rec.q ilike 'select %' or rec.q ilike 'with %' ) THEN
--RAISE WARNING 'Skipping %', rec.q;
CONTINUE;
END IF;
BEGIN
EXECUTE 'EXPLAIN (FORMAT XML, VERBOSE) ' || rec.q INTO STRICT exp;
EXCEPTION WHEN others THEN
-- TODO: if error is 'relation "xxxxxx" does not exist', take xxxxxx as
-- the affected table ?
RAISE WARNING 'CDB_QueryTables cannot explain query: % (%: %)', rec.q, SQLSTATE, SQLERRM;
RAISE EXCEPTION '%', SQLERRM;
CONTINUE;
END;
-- Now need to extract all values of <Relation-Name>
-- RAISE DEBUG 'Explain: %', exp;
FOR rec2 IN WITH
inp AS (
SELECT
xpath('//x:Relation-Name/text()', exp, ARRAY[ARRAY['x', 'http://www.postgresql.org/2009/explain']]) as x,
xpath('//x:Schema/text()', exp, ARRAY[ARRAY['x', 'http://www.postgresql.org/2009/explain']]) as s
)
SELECT unnest(x)::name as p, unnest(s)::name as sc from inp
LOOP
-- RAISE DEBUG 'tab: %', rec2.p;
-- RAISE DEBUG 'sc: %', rec2.sc;
tables := array_append(tables, (rec2.sc || '.' || rec2.p)::name);
END LOOP;
-- RAISE DEBUG 'Tables: %', tables;
END LOOP;
-- RAISE DEBUG 'Tables: %', tables;
-- Remove duplicates and sort by name
IF array_upper(tables, 1) > 0 THEN
WITH dist as ( SELECT DISTINCT unnest(tables)::text as p ORDER BY p )
SELECT array_agg(p) from dist into tables;
END IF;
--RAISE DEBUG 'Tables: %', tables;
return tables;
END
$$ LANGUAGE 'plpgsql' VOLATILE STRICT;