postgresql/contrib/pageinspect/sql/gist.sql
Heikki Linnakangas 5abca4b1cd Fix test failure with wal_level=minimal.
The newly-added gist pageinspect test prints the LSNs of GiST pages,
expecting them all to be 1 (GistBuildLSN). But with wal_level=minimal,
they got updated by the whole-relation WAL-logging at commit. Fix by
wrapping the problematic tests in the same transaction with the CREATE
INDEX.

Per buildfarm failure on thorntail.

Discussion: https://www.postgresql.org/message-id/3B4F97E5-40FB-4142-8CAA-B301CDFBF982%40iki.fi
2021-01-13 20:58:51 +02:00

30 lines
1.4 KiB
PL/PgSQL

-- The gist_page_opaque_info() function prints the page's LSN. Normally,
-- that's constant 1 (GistBuildLSN) on every page of a freshly built GiST
-- index. But with wal_level=minimal, the whole relation is dumped to WAL at
-- the end of the transaction if it's smaller than wal_skip_threshold, which
-- updates the LSNs. Wrap the tests on gist_page_opaque_info() in the
-- same transaction with the CREATE INDEX so that we see the LSNs before
-- they are possibly overwritten at end of transaction.
BEGIN;
-- Create a test table and GiST index.
CREATE TABLE test_gist AS SELECT point(i,i) p, i::text t FROM
generate_series(1,1000) i;
CREATE INDEX test_gist_idx ON test_gist USING gist (p);
-- Page 0 is the root, the rest are leaf pages
SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 0));
SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 1));
SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
COMMIT;
SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 0), 'test_gist_idx');
SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 1), 'test_gist_idx') LIMIT 5;
-- gist_page_items_bytea prints the raw key data as a bytea. The output of that is
-- platform-dependent (endianess), so omit the actual key data from the output.
SELECT itemoffset, ctid, itemlen FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 0));
DROP TABLE test_gist;