-- Hypothetically hiding existing indexes tests
-- Remove all the hypothetical indexes if any
SELECT hypopg_reset();
 hypopg_reset 
--------------
 
(1 row)

-- The EXPLAIN initial state
SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'hypo_id_idx';
 count 
-------
     0
(1 row)

-- Create real index in hypo and use this index
CREATE INDEX hypo_id_idx ON hypo(id);
SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'hypo_id_idx';
 count 
-------
     1
(1 row)

-- Should be zero
SELECT COUNT(*) FROM hypopg_hidden_indexes();
 count 
-------
     0
(1 row)

-- The hypo_id_idx index should not be used
SELECT hypopg_hide_index('hypo_id_idx'::regclass);
 hypopg_hide_index 
-------------------
 t
(1 row)

SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'hypo_id_idx';
 count 
-------
     0
(1 row)

-- Should be only one record
SELECT COUNT(*) FROM hypopg_hidden_indexes();
 count 
-------
     1
(1 row)

SELECT table_name,index_name FROM hypopg_hidden_indexes;
 table_name | index_name  
------------+-------------
 hypo       | hypo_id_idx
(1 row)

-- Create the real index again and
-- EXPLAIN should use this index instead of the previous one
CREATE index hypo_id_val_idx ON hypo(id, val);
SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'hypo_id_val_idx';
 count 
-------
     1
(1 row)

-- Shouldn't use any index
SELECT hypopg_hide_index('hypo_id_val_idx'::regclass);
 hypopg_hide_index 
-------------------
 t
(1 row)

SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'hypo_id_val_idx';
 count 
-------
     0
(1 row)

-- Should be two records
SELECT table_name,index_name FROM hypopg_hidden_indexes;
 table_name |   index_name    
------------+-----------------
 hypo       | hypo_id_idx
 hypo       | hypo_id_val_idx
(2 rows)

-- Try to add one repeatedly or add another wrong index oid
SELECT hypopg_hide_index('hypo_id_idx'::regclass);
 hypopg_hide_index 
-------------------
 f
(1 row)

SELECT hypopg_hide_index('hypo'::regclass);
 hypopg_hide_index 
-------------------
 f
(1 row)

SELECT hypopg_hide_index(0);
 hypopg_hide_index 
-------------------
 f
(1 row)

-- Also of course can be used to hide hypothetical indexes
SELECT COUNT(*) FROM hypopg_create_index('create index on hypo(id,val);');
 count 
-------
     1
(1 row)

SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'Index.*<\d+>btree_hypo.*';
 count 
-------
     1
(1 row)

SELECT hypopg_hide_index((SELECT indexrelid FROM hypopg_list_indexes LIMIT 1));
 hypopg_hide_index 
-------------------
 t
(1 row)

SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'Index.*<\d+>btree_hypo.*';
 count 
-------
     0
(1 row)

-- Should be only three records
SELECT COUNT(*) FROM hypopg_hidden_indexes;
 count 
-------
     3
(1 row)

-- Hypothetical indexes should be unhidden when deleting
SELECT hypopg_drop_index((SELECT indexrelid FROM hypopg_list_indexes LIMIT 1));
 hypopg_drop_index 
-------------------
 t
(1 row)

-- Should become two records
SELECT COUNT(*) FROM hypopg_hidden_indexes;
 count 
-------
     2
(1 row)

-- Hypopg_reset can also unhidden the hidden indexes
-- due to the deletion of hypothetical indexes.
SELECT COUNT(*) FROM hypopg_create_index('create index on hypo(id,val);');
 count 
-------
     1
(1 row)

SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'Index.*<\d+>btree_hypo.*';
 count 
-------
     1
(1 row)

SELECT hypopg_hide_index((SELECT indexrelid FROM hypopg_list_indexes LIMIT 1));
 hypopg_hide_index 
-------------------
 t
(1 row)

-- Changed from three records to two records.
SELECT COUNT(*) FROM hypopg_hidden_indexes;
 count 
-------
     3
(1 row)

SELECT hypopg_reset();
 hypopg_reset 
--------------
 
(1 row)

SELECT COUNT(*) FROM hypopg_hidden_indexes;
 count 
-------
     2
(1 row)

-- Unhide an index
SELECT hypopg_unhide_index('hypo_id_idx'::regclass);
 hypopg_unhide_index 
---------------------
 t
(1 row)

SELECT COUNT(*) FROM do_explain('SELECT * FROM hypo WHERE id = 1') e
WHERE e ~ 'hypo_id_idx';
 count 
-------
     1
(1 row)

-- Should become one record
SELECT table_name,index_name FROM hypopg_hidden_indexes;
 table_name |   index_name    
------------+-----------------
 hypo       | hypo_id_val_idx
(1 row)

-- Try to delete one repeatedly or delete another wrong index oid
SELECT hypopg_unhide_index('hypo_id_idx'::regclass);
 hypopg_unhide_index 
---------------------
 f
(1 row)

SELECT hypopg_unhide_index('hypo'::regclass);
 hypopg_unhide_index 
---------------------
 f
(1 row)

SELECT hypopg_unhide_index(0);
 hypopg_unhide_index 
---------------------
 f
(1 row)

-- Should still have one record
SELECT table_name,index_name FROM hypopg_hidden_indexes;
 table_name |   index_name    
------------+-----------------
 hypo       | hypo_id_val_idx
(1 row)

-- Unhide all indexes
SELECT hypopg_unhide_all_indexes();
 hypopg_unhide_all_indexes 
---------------------------
 
(1 row)

-- Should change back to the original zero
SELECT COUNT(*) FROM hypopg_hidden_indexes();
 count 
-------
     0
(1 row)

-- Clean real indexes and hypothetical indexes
DROP INDEX hypo_id_idx;
DROP INDEX hypo_id_val_idx;
SELECT hypopg_reset();
 hypopg_reset 
--------------
 
(1 row)