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-- hypothetical indexes using INCLUDE keyword, pg11+
-- Remove all the hypothetical indexes if any
SELECT hypopg_reset();
hypopg_reset
--------------
(1 row)
-- Make sure stats and visibility map are up to date
VACUUM ANALYZE hypo;
-- Should not use hypothetical index
-- Create normal index
SELECT COUNT(*) AS NB
FROM hypopg_create_index('CREATE INDEX ON hypo (id)');
nb
----
1
(1 row)
-- Should use hypothetical index using a regular Index Scan
SELECT COUNT(*) FROM do_explain('SELECT val FROM hypo WHERE id = 1') e
WHERE e ~ 'Index Scan.*<\d+>btree_hypo.*';
count
-------
1
(1 row)
-- Remove all the hypothetical indexes
SELECT hypopg_reset();
hypopg_reset
--------------
(1 row)
-- Create INCLUDE index
SELECT COUNT(*) AS NB
FROM hypopg_create_index('CREATE INDEX ON hypo (id) INCLUDE (val, "Id2")');
nb
----
1
(1 row)
-- Should use hypothetical index using an Index Only Scan
SELECT COUNT(*) FROM do_explain('SELECT val FROM hypo WHERE id = 1') e
WHERE e ~ 'Index Only Scan.*<\d+>btree_hypo.*';
count
-------
1
(1 row)
-- Deparse the index DDL
SELECT hypopg_get_indexdef(indexrelid) FROM hypopg();
hypopg_get_indexdef
-------------------------------------------------------------------
CREATE INDEX ON public.hypo USING btree (id) INCLUDE (val, "Id2")
(1 row)
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