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|
-- These tests display internal details that would not be stable under
-- debug_parallel_query, so make sure that option is disabled.
SET debug_parallel_query = off;
-- Make sure that we don't print any JIT-related information, as that
-- would also make results unstable.
SET jit = off;
-- These options do not exist, so these queries should all fail.
EXPLAIN (DEBUFF) SELECT 1;
ERROR: unrecognized EXPLAIN option "debuff"
LINE 1: EXPLAIN (DEBUFF) SELECT 1;
^
EXPLAIN (DEBUG) SELECT 1;
ERROR: unrecognized EXPLAIN option "debug"
LINE 1: EXPLAIN (DEBUG) SELECT 1;
^
EXPLAIN (RANGE_TABLE) SELECT 1;
ERROR: unrecognized EXPLAIN option "range_table"
LINE 1: EXPLAIN (RANGE_TABLE) SELECT 1;
^
-- Load the module that creates the options.
LOAD 'pg_overexplain';
-- The first option still does not exist, but the others do.
EXPLAIN (DEBUFF) SELECT 1;
ERROR: unrecognized EXPLAIN option "debuff"
LINE 1: EXPLAIN (DEBUFF) SELECT 1;
^
EXPLAIN (DEBUG) SELECT 1;
QUERY PLAN
------------------------------------------
Result (cost=0.00..0.01 rows=1 width=4)
Disabled Nodes: 0
Parallel Safe: false
Plan Node ID: 0
PlannedStmt:
Command Type: select
Flags: canSetTag
Subplans Needing Rewind: none
Relation OIDs: none
Executor Parameter Types: none
Parse Location: 0 to end
(11 rows)
EXPLAIN (RANGE_TABLE) SELECT 1;
QUERY PLAN
------------------------------------------
Result (cost=0.00..0.01 rows=1 width=4)
RTI 1 (result):
Eref: "*RESULT*" ()
(3 rows)
-- Create a partitioned table.
CREATE TABLE vegetables (id serial, name text, genus text)
PARTITION BY LIST (genus);
CREATE TABLE daucus PARTITION OF vegetables FOR VALUES IN ('daucus');
CREATE TABLE brassica PARTITION OF vegetables FOR VALUES IN ('brassica');
INSERT INTO vegetables (name, genus)
VALUES ('carrot', 'daucus'), ('bok choy', 'brassica'),
('brocooli', 'brassica'), ('cauliflower', 'brassica'),
('cabbage', 'brassica'), ('kohlrabi', 'brassica'),
('rutabaga', 'brassica'), ('turnip', 'brassica');
VACUUM ANALYZE vegetables;
-- We filter relation OIDs out of the test output in order to avoid
-- test instability. This is currently only needed for EXPLAIN (DEBUG), not
-- EXPLAIN (RANGE_TABLE). Also suppress actual row counts, which are not
-- stable (e.g. 1/8 is 0.12 on some buildfarm machines and 0.13 on others).
CREATE FUNCTION explain_filter(text) RETURNS SETOF text
LANGUAGE plpgsql AS
$$
DECLARE
ln text;
BEGIN
FOR ln IN EXECUTE $1
LOOP
ln := regexp_replace(ln, 'Relation OIDs:( \m\d+\M)+',
'Relation OIDs: NNN...', 'g');
ln := regexp_replace(ln, '<Relation-OIDs>( ?\m\d+\M)+</Relation-OIDs>',
'<Relation-OIDs>NNN...</Relation-OIDs>', 'g');
ln := regexp_replace(ln, 'actual rows=\d+\.\d+',
'actual rows=N.NN', 'g');
RETURN NEXT ln;
END LOOP;
END;
$$;
-- Test with both options together and an aggregate.
SELECT explain_filter($$
EXPLAIN (DEBUG, RANGE_TABLE, COSTS OFF)
SELECT genus, array_agg(name ORDER BY name) FROM vegetables GROUP BY genus
$$);
explain_filter
-----------------------------------------------------
GroupAggregate
Group Key: vegetables.genus
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 0
-> Sort
Sort Key: vegetables.genus, vegetables.name
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 1
-> Append
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 2
Append RTIs: 1
-> Seq Scan on brassica vegetables_1
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 3
Scan RTI: 3
-> Seq Scan on daucus vegetables_2
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 4
Scan RTI: 4
PlannedStmt:
Command Type: select
Flags: canSetTag
Subplans Needing Rewind: none
Relation OIDs: NNN...
Executor Parameter Types: none
Parse Location: 0 to end
RTI 1 (relation, inherited, in-from-clause):
Eref: vegetables (id, name, genus)
Relation: vegetables
Relation Kind: partitioned_table
Relation Lock Mode: AccessShareLock
Permission Info Index: 1
RTI 2 (group):
Eref: "*GROUP*" (genus)
RTI 3 (relation, in-from-clause):
Alias: vegetables (id, name, genus)
Eref: vegetables (id, name, genus)
Relation: brassica
Relation Kind: relation
Relation Lock Mode: AccessShareLock
RTI 4 (relation, in-from-clause):
Alias: vegetables (id, name, genus)
Eref: vegetables (id, name, genus)
Relation: daucus
Relation Kind: relation
Relation Lock Mode: AccessShareLock
Unprunable RTIs: 1 3 4
(53 rows)
-- Test a different output format.
SELECT explain_filter($$
EXPLAIN (DEBUG, RANGE_TABLE, FORMAT XML, COSTS OFF)
SELECT genus, array_agg(name ORDER BY name) FROM vegetables GROUP BY genus
$$);
explain_filter
---------------------------------------------------------------------
<explain xmlns="http://www.postgresql.org/2009/explain"> +
<Query> +
<Plan> +
<Node-Type>Aggregate</Node-Type> +
<Strategy>Sorted</Strategy> +
<Partial-Mode>Simple</Partial-Mode> +
<Parallel-Aware>false</Parallel-Aware> +
<Async-Capable>false</Async-Capable> +
<Disabled>false</Disabled> +
<Group-Key> +
<Item>vegetables.genus</Item> +
</Group-Key> +
<Disabled-Nodes>0</Disabled-Nodes> +
<Parallel-Safe>true</Parallel-Safe> +
<Plan-Node-ID>0</Plan-Node-ID> +
<extParam>none</extParam> +
<allParam>none</allParam> +
<Plans> +
<Plan> +
<Node-Type>Sort</Node-Type> +
<Parent-Relationship>Outer</Parent-Relationship> +
<Parallel-Aware>false</Parallel-Aware> +
<Async-Capable>false</Async-Capable> +
<Disabled>false</Disabled> +
<Sort-Key> +
<Item>vegetables.genus</Item> +
<Item>vegetables.name</Item> +
</Sort-Key> +
<Disabled-Nodes>0</Disabled-Nodes> +
<Parallel-Safe>true</Parallel-Safe> +
<Plan-Node-ID>1</Plan-Node-ID> +
<extParam>none</extParam> +
<allParam>none</allParam> +
<Plans> +
<Plan> +
<Node-Type>Append</Node-Type> +
<Parent-Relationship>Outer</Parent-Relationship> +
<Parallel-Aware>false</Parallel-Aware> +
<Async-Capable>false</Async-Capable> +
<Disabled>false</Disabled> +
<Disabled-Nodes>0</Disabled-Nodes> +
<Parallel-Safe>true</Parallel-Safe> +
<Plan-Node-ID>2</Plan-Node-ID> +
<extParam>none</extParam> +
<allParam>none</allParam> +
<Append-RTIs>1</Append-RTIs> +
<Subplans-Removed>0</Subplans-Removed> +
<Plans> +
<Plan> +
<Node-Type>Seq Scan</Node-Type> +
<Parent-Relationship>Member</Parent-Relationship>+
<Parallel-Aware>false</Parallel-Aware> +
<Async-Capable>false</Async-Capable> +
<Relation-Name>brassica</Relation-Name> +
<Alias>vegetables_1</Alias> +
<Disabled>false</Disabled> +
<Disabled-Nodes>0</Disabled-Nodes> +
<Parallel-Safe>true</Parallel-Safe> +
<Plan-Node-ID>3</Plan-Node-ID> +
<extParam>none</extParam> +
<allParam>none</allParam> +
<Scan-RTI>3</Scan-RTI> +
</Plan> +
<Plan> +
<Node-Type>Seq Scan</Node-Type> +
<Parent-Relationship>Member</Parent-Relationship>+
<Parallel-Aware>false</Parallel-Aware> +
<Async-Capable>false</Async-Capable> +
<Relation-Name>daucus</Relation-Name> +
<Alias>vegetables_2</Alias> +
<Disabled>false</Disabled> +
<Disabled-Nodes>0</Disabled-Nodes> +
<Parallel-Safe>true</Parallel-Safe> +
<Plan-Node-ID>4</Plan-Node-ID> +
<extParam>none</extParam> +
<allParam>none</allParam> +
<Scan-RTI>4</Scan-RTI> +
</Plan> +
</Plans> +
</Plan> +
</Plans> +
</Plan> +
</Plans> +
</Plan> +
<PlannedStmt> +
<Command-Type>select</Command-Type> +
<Flags>canSetTag</Flags> +
<Subplans-Needing-Rewind>none</Subplans-Needing-Rewind> +
<Relation-OIDs>NNN...</Relation-OIDs> +
<Executor-Parameter-Types>none</Executor-Parameter-Types> +
<Parse-Location>0 to end</Parse-Location> +
</PlannedStmt> +
<Range-Table> +
<Range-Table-Entry> +
<RTI>1</RTI> +
<Kind>relation</Kind> +
<Inherited>true</Inherited> +
<In-From-Clause>true</In-From-Clause> +
<Eref>vegetables (id, name, genus)</Eref> +
<Relation>vegetables</Relation> +
<Relation-Kind>partitioned_table</Relation-Kind> +
<Relation-Lock-Mode>AccessShareLock</Relation-Lock-Mode> +
<Permission-Info-Index>1</Permission-Info-Index> +
<Security-Barrier>false</Security-Barrier> +
<Lateral>false</Lateral> +
</Range-Table-Entry> +
<Range-Table-Entry> +
<RTI>2</RTI> +
<Kind>group</Kind> +
<Inherited>false</Inherited> +
<In-From-Clause>false</In-From-Clause> +
<Eref>"*GROUP*" (genus)</Eref> +
<Security-Barrier>false</Security-Barrier> +
<Lateral>false</Lateral> +
</Range-Table-Entry> +
<Range-Table-Entry> +
<RTI>3</RTI> +
<Kind>relation</Kind> +
<Inherited>false</Inherited> +
<In-From-Clause>true</In-From-Clause> +
<Alias>vegetables (id, name, genus)</Alias> +
<Eref>vegetables (id, name, genus)</Eref> +
<Relation>brassica</Relation> +
<Relation-Kind>relation</Relation-Kind> +
<Relation-Lock-Mode>AccessShareLock</Relation-Lock-Mode> +
<Security-Barrier>false</Security-Barrier> +
<Lateral>false</Lateral> +
</Range-Table-Entry> +
<Range-Table-Entry> +
<RTI>4</RTI> +
<Kind>relation</Kind> +
<Inherited>false</Inherited> +
<In-From-Clause>true</In-From-Clause> +
<Alias>vegetables (id, name, genus)</Alias> +
<Eref>vegetables (id, name, genus)</Eref> +
<Relation>daucus</Relation> +
<Relation-Kind>relation</Relation-Kind> +
<Relation-Lock-Mode>AccessShareLock</Relation-Lock-Mode> +
<Security-Barrier>false</Security-Barrier> +
<Lateral>false</Lateral> +
</Range-Table-Entry> +
<Unprunable-RTIs>1 3 4</Unprunable-RTIs> +
<Result-RTIs>none</Result-RTIs> +
</Range-Table> +
</Query> +
</explain>
(1 row)
-- Test just the DEBUG option. Verify that it shows information about
-- disabled nodes, parallel safety, and the parallelModeNeeded flag.
SET enable_seqscan = false;
SET debug_parallel_query = true;
SELECT explain_filter($$
EXPLAIN (DEBUG, COSTS OFF)
SELECT genus, array_agg(name ORDER BY name) FROM vegetables GROUP BY genus
$$);
explain_filter
-----------------------------------------------------------
Gather
Workers Planned: 1
Single Copy: true
Disabled Nodes: 0
Parallel Safe: false
Plan Node ID: 0
-> GroupAggregate
Group Key: vegetables.genus
Disabled Nodes: 2
Parallel Safe: true
Plan Node ID: 1
-> Sort
Sort Key: vegetables.genus, vegetables.name
Disabled Nodes: 2
Parallel Safe: true
Plan Node ID: 2
-> Append
Disabled Nodes: 2
Parallel Safe: true
Plan Node ID: 3
-> Seq Scan on brassica vegetables_1
Disabled: true
Disabled Nodes: 1
Parallel Safe: true
Plan Node ID: 4
-> Seq Scan on daucus vegetables_2
Disabled: true
Disabled Nodes: 1
Parallel Safe: true
Plan Node ID: 5
PlannedStmt:
Command Type: select
Flags: canSetTag, parallelModeNeeded
Subplans Needing Rewind: none
Relation OIDs: NNN...
Executor Parameter Types: none
Parse Location: 0 to end
(37 rows)
SET debug_parallel_query = false;
RESET enable_seqscan;
-- Test the DEBUG option with a non-SELECT query, and also verify that the
-- hasReturning flag is shown.
SELECT explain_filter($$
EXPLAIN (DEBUG, COSTS OFF)
INSERT INTO vegetables (name, genus)
VALUES ('Brotero''s carrot', 'brassica') RETURNING id
$$);
explain_filter
----------------------------------
Insert on vegetables
Disabled Nodes: 0
Parallel Safe: false
Plan Node ID: 0
-> Result
Disabled Nodes: 0
Parallel Safe: false
Plan Node ID: 1
PlannedStmt:
Command Type: insert
Flags: hasReturning, canSetTag
Subplans Needing Rewind: none
Relation OIDs: NNN...
Executor Parameter Types: 0
Parse Location: 0 to end
(15 rows)
-- Create an index, and then attempt to force a nested loop with inner index
-- scan so that we can see parameter-related information. Also, let's try
-- actually running the query, but try to suppress potentially variable output.
CREATE INDEX ON vegetables (id);
ANALYZE vegetables;
SET enable_hashjoin = false;
SET enable_material = false;
SET enable_mergejoin = false;
SET enable_seqscan = false;
SELECT explain_filter($$
EXPLAIN (BUFFERS OFF, COSTS OFF, SUMMARY OFF, TIMING OFF, ANALYZE, DEBUG)
SELECT * FROM vegetables v1, vegetables v2 WHERE v1.id = v2.id;
$$);
explain_filter
------------------------------------------------------------------------------------------
Nested Loop (actual rows=N.NN loops=1)
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 0
-> Append (actual rows=N.NN loops=1)
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 1
-> Index Scan using brassica_id_idx on brassica v1_1 (actual rows=N.NN loops=1)
Index Searches: 1
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 2
-> Index Scan using daucus_id_idx on daucus v1_2 (actual rows=N.NN loops=1)
Index Searches: 1
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 3
-> Append (actual rows=N.NN loops=8)
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 4
extParam: 0
allParam: 0
-> Index Scan using brassica_id_idx on brassica v2_1 (actual rows=N.NN loops=8)
Index Cond: (id = v1.id)
Index Searches: 8
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 5
extParam: 0
allParam: 0
-> Index Scan using daucus_id_idx on daucus v2_2 (actual rows=N.NN loops=8)
Index Cond: (id = v1.id)
Index Searches: 8
Disabled Nodes: 0
Parallel Safe: true
Plan Node ID: 6
extParam: 0
allParam: 0
PlannedStmt:
Command Type: select
Flags: canSetTag
Subplans Needing Rewind: none
Relation OIDs: NNN...
Executor Parameter Types: 23
Parse Location: 0 to end
(47 rows)
RESET enable_hashjoin;
RESET enable_material;
RESET enable_mergejoin;
RESET enable_seqscan;
-- Test the RANGE_TABLE option with a case that allows partition pruning.
EXPLAIN (RANGE_TABLE, COSTS OFF)
SELECT * FROM vegetables WHERE genus = 'daucus';
QUERY PLAN
----------------------------------------------
Seq Scan on daucus vegetables
Filter: (genus = 'daucus'::text)
Scan RTI: 2
RTI 1 (relation, inherited, in-from-clause):
Eref: vegetables (id, name, genus)
Relation: vegetables
Relation Kind: partitioned_table
Relation Lock Mode: AccessShareLock
Permission Info Index: 1
RTI 2 (relation, in-from-clause):
Alias: vegetables (id, name, genus)
Eref: vegetables (id, name, genus)
Relation: daucus
Relation Kind: relation
Relation Lock Mode: AccessShareLock
Unprunable RTIs: 1 2
(16 rows)
-- Also test a case that involves a write.
EXPLAIN (RANGE_TABLE, COSTS OFF)
INSERT INTO vegetables (name, genus) VALUES ('broccoflower', 'brassica');
QUERY PLAN
----------------------------------------
Insert on vegetables
Nominal RTI: 1
Exclude Relation RTI: 0
-> Result
RTI 1 (relation):
Eref: vegetables (id, name, genus)
Relation: vegetables
Relation Kind: partitioned_table
Relation Lock Mode: RowExclusiveLock
Permission Info Index: 1
RTI 2 (result):
Eref: "*RESULT*" ()
Unprunable RTIs: 1
Result RTIs: 1
(14 rows)
|
