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|
--
-- SELECT statements
--
CREATE EXTENSION pg_stat_plans;
SELECT pg_stat_plans_reset() IS NOT NULL AS t;
t
---
t
(1 row)
--
-- simple statements
--
SELECT 1 FROM pg_class LIMIT 1;
?column?
----------
1
(1 row)
SELECT 1 FROM pg_class WHERE relname = 'pg_class';
?column?
----------
1
(1 row)
SET enable_indexscan = off;
SELECT 1 FROM pg_class WHERE relname = 'pg_class';
?column?
----------
1
(1 row)
SET enable_indexscan = on;
SELECT plan, calls FROM pg_stat_plans ORDER BY plan COLLATE "C";
plan | calls
--------------------------------------------------------------+-------
Bitmap Heap Scan on pg_class +| 1
Recheck Cond: (relname = 'pg_class'::name) +|
-> Bitmap Index Scan on pg_class_relname_nsp_index +|
Index Cond: (relname = 'pg_class'::name) |
Index Only Scan using pg_class_relname_nsp_index on pg_class+| 1
Index Cond: (relname = 'pg_class'::name) |
Limit +| 1
-> Seq Scan on pg_class |
Result | 1
Sort +| 0
Sort Key: pg_stat_plans.plan COLLATE "C" +|
-> Function Scan on pg_stat_plans |
(5 rows)
SELECT pg_stat_plans_reset() IS NOT NULL AS t;
t
---
t
(1 row)
--
-- subplans and CTEs
--
WITH x AS MATERIALIZED (SELECT 1)
SELECT * FROM x;
?column?
----------
1
(1 row)
SELECT a.attname,
(SELECT pg_catalog.pg_get_expr(d.adbin, d.adrelid)
FROM pg_catalog.pg_attrdef d
WHERE d.adrelid = a.attrelid AND d.adnum = a.attnum AND a.atthasdef)
FROM pg_catalog.pg_attribute a
WHERE a.attrelid = 'pg_class'::regclass
ORDER BY attnum LIMIT 1;
attname | pg_get_expr
----------+-------------
tableoid |
(1 row)
SELECT plan, calls FROM pg_stat_plans ORDER BY plan COLLATE "C";
plan | calls
-------------------------------------------------------------------------------+-------
CTE Scan on x +| 1
CTE x +|
-> Result |
Limit +| 1
-> Index Scan using pg_attribute_relid_attnum_index on pg_attribute a +|
Index Cond: (attrelid = '1259'::oid) +|
SubPlan 1 +|
-> Result +|
One-Time Filter: a.atthasdef +|
-> Seq Scan on pg_attrdef d +|
Filter: ((adrelid = a.attrelid) AND (adnum = a.attnum)) |
Result | 1
Sort +| 0
Sort Key: pg_stat_plans.plan COLLATE "C" +|
-> Function Scan on pg_stat_plans |
(4 rows)
SELECT pg_stat_plans_reset() IS NOT NULL AS t;
t
---
t
(1 row)
--
-- partitoning
--
create table lp (a char) partition by list (a);
create table lp_default partition of lp default;
create table lp_ef partition of lp for values in ('e', 'f');
create table lp_ad partition of lp for values in ('a', 'd');
create table lp_bc partition of lp for values in ('b', 'c');
create table lp_g partition of lp for values in ('g');
create table lp_null partition of lp for values in (null);
select * from lp;
a
---
(0 rows)
select * from lp where a > 'a' and a < 'd';
a
---
(0 rows)
select * from lp where a > 'a' and a <= 'd';
a
---
(0 rows)
select * from lp where a = 'a';
a
---
(0 rows)
select * from lp where 'a' = a; /* commuted */
a
---
(0 rows)
select * from lp where a is not null;
a
---
(0 rows)
select * from lp where a is null;
a
---
(0 rows)
select * from lp where a = 'a' or a = 'c';
a
---
(0 rows)
select * from lp where a is not null and (a = 'a' or a = 'c');
a
---
(0 rows)
select * from lp where a <> 'g';
a
---
(0 rows)
select * from lp where a <> 'a' and a <> 'd';
a
---
(0 rows)
select * from lp where a not in ('a', 'd');
a
---
(0 rows)
SELECT plan, calls FROM pg_stat_plans ORDER BY plan COLLATE "C";
plan | calls
--------------------------------------------------------------------------------+-------
Append +| 1
-> Seq Scan on lp_ad lp_1 +|
Filter: ((a = 'a'::bpchar) OR (a = 'c'::bpchar)) +|
-> Seq Scan on lp_bc lp_2 +|
Filter: ((a = 'a'::bpchar) OR (a = 'c'::bpchar)) |
Append +| 1
-> Seq Scan on lp_ad lp_1 +|
Filter: ((a > 'a'::bpchar) AND (a <= 'd'::bpchar)) +|
-> Seq Scan on lp_bc lp_2 +|
Filter: ((a > 'a'::bpchar) AND (a <= 'd'::bpchar)) +|
-> Seq Scan on lp_default lp_3 +|
Filter: ((a > 'a'::bpchar) AND (a <= 'd'::bpchar)) |
Append +| 1
-> Seq Scan on lp_ad lp_1 +|
Filter: ((a IS NOT NULL) AND ((a = 'a'::bpchar) OR (a = 'c'::bpchar)))+|
-> Seq Scan on lp_bc lp_2 +|
Filter: ((a IS NOT NULL) AND ((a = 'a'::bpchar) OR (a = 'c'::bpchar))) |
Append +| 1
-> Seq Scan on lp_ad lp_1 +|
Filter: (a <> 'g'::bpchar) +|
-> Seq Scan on lp_bc lp_2 +|
Filter: (a <> 'g'::bpchar) +|
-> Seq Scan on lp_ef lp_3 +|
Filter: (a <> 'g'::bpchar) +|
-> Seq Scan on lp_default lp_4 +|
Filter: (a <> 'g'::bpchar) |
Append +| 1
-> Seq Scan on lp_ad lp_1 +|
Filter: (a IS NOT NULL) +|
-> Seq Scan on lp_bc lp_2 +|
Filter: (a IS NOT NULL) +|
-> Seq Scan on lp_ef lp_3 +|
Filter: (a IS NOT NULL) +|
-> Seq Scan on lp_g lp_4 +|
Filter: (a IS NOT NULL) +|
-> Seq Scan on lp_default lp_5 +|
Filter: (a IS NOT NULL) |
Append +| 1
-> Seq Scan on lp_ad lp_1 +|
-> Seq Scan on lp_bc lp_2 +|
-> Seq Scan on lp_ef lp_3 +|
-> Seq Scan on lp_g lp_4 +|
-> Seq Scan on lp_null lp_5 +|
-> Seq Scan on lp_default lp_6 |
Append +| 1
-> Seq Scan on lp_bc lp_1 +|
Filter: ((a <> 'a'::bpchar) AND (a <> 'd'::bpchar)) +|
-> Seq Scan on lp_ef lp_2 +|
Filter: ((a <> 'a'::bpchar) AND (a <> 'd'::bpchar)) +|
-> Seq Scan on lp_g lp_3 +|
Filter: ((a <> 'a'::bpchar) AND (a <> 'd'::bpchar)) +|
-> Seq Scan on lp_default lp_4 +|
Filter: ((a <> 'a'::bpchar) AND (a <> 'd'::bpchar)) |
Append +| 1
-> Seq Scan on lp_bc lp_1 +|
Filter: ((a > 'a'::bpchar) AND (a < 'd'::bpchar)) +|
-> Seq Scan on lp_default lp_2 +|
Filter: ((a > 'a'::bpchar) AND (a < 'd'::bpchar)) |
Append +| 1
-> Seq Scan on lp_bc lp_1 +|
Filter: (a <> ALL ('{a,d}'::bpchar[])) +|
-> Seq Scan on lp_ef lp_2 +|
Filter: (a <> ALL ('{a,d}'::bpchar[])) +|
-> Seq Scan on lp_g lp_3 +|
Filter: (a <> ALL ('{a,d}'::bpchar[])) +|
-> Seq Scan on lp_default lp_4 +|
Filter: (a <> ALL ('{a,d}'::bpchar[])) |
Result | 1
Seq Scan on lp_ad lp +| 1
Filter: ('a'::bpchar = a) |
Seq Scan on lp_ad lp +| 1
Filter: (a = 'a'::bpchar) |
Seq Scan on lp_null lp +| 1
Filter: (a IS NULL) |
Sort +| 0
Sort Key: pg_stat_plans.plan COLLATE "C" +|
-> Function Scan on pg_stat_plans |
(14 rows)
SELECT pg_stat_plans_reset() IS NOT NULL AS t;
t
---
t
(1 row)
|
