diff --git a/src/backend/optimizer/plan/initsplan.c b/src/backend/optimizer/plan/initsplan.c index 2cb0ae6d659..1d1aa27d450 100644 --- a/src/backend/optimizer/plan/initsplan.c +++ b/src/backend/optimizer/plan/initsplan.c @@ -3091,6 +3091,15 @@ bool restriction_is_always_true(PlannerInfo *root, RestrictInfo *restrictinfo) { + /* + * For a clone clause, we don't have a reliable way to determine if the + * input expression of a NullTest is non-nullable: nullingrel bits in + * clone clauses may not reflect reality, so we dare not draw conclusions + * from clones about whether Vars are guaranteed not-null. + */ + if (restrictinfo->has_clone || restrictinfo->is_clone) + return false; + /* Check for NullTest qual */ if (IsA(restrictinfo->clause, NullTest)) { @@ -3140,6 +3149,15 @@ bool restriction_is_always_false(PlannerInfo *root, RestrictInfo *restrictinfo) { + /* + * For a clone clause, we don't have a reliable way to determine if the + * input expression of a NullTest is non-nullable: nullingrel bits in + * clone clauses may not reflect reality, so we dare not draw conclusions + * from clones about whether Vars are guaranteed not-null. + */ + if (restrictinfo->has_clone || restrictinfo->is_clone) + return false; + /* Check for NullTest qual */ if (IsA(restrictinfo->clause, NullTest)) { diff --git a/src/test/regress/expected/predicate.out b/src/test/regress/expected/predicate.out index 965a3a76161..b79037748b7 100644 --- a/src/test/regress/expected/predicate.out +++ b/src/test/regress/expected/predicate.out @@ -97,55 +97,50 @@ SELECT * FROM pred_tab t WHERE t.b IS NULL OR t.c IS NULL; -- and b) its Var is not nullable by any outer joins EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL; - QUERY PLAN -------------------------------------------------- + LEFT JOIN pred_tab t2 ON t1.a IS NOT NULL; + QUERY PLAN +------------------------------------- Nested Loop Left Join -> Seq Scan on pred_tab t1 -> Materialize - -> Nested Loop Left Join - -> Seq Scan on pred_tab t2 - -> Materialize - -> Seq Scan on pred_tab t3 -(7 rows) + -> Seq Scan on pred_tab t2 +(4 rows) -- Ensure the IS_NOT_NULL qual is not ignored when columns are made nullable -- by an outer join EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON t1.a = 1 + FULL JOIN pred_tab t2 ON t1.a = t2.a LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL; QUERY PLAN ------------------------------------------- Nested Loop Left Join Join Filter: (t2.a IS NOT NULL) - -> Nested Loop Left Join - Join Filter: (t1.a = 1) - -> Seq Scan on pred_tab t1 - -> Materialize + -> Merge Full Join + Merge Cond: (t1.a = t2.a) + -> Sort + Sort Key: t1.a + -> Seq Scan on pred_tab t1 + -> Sort + Sort Key: t2.a -> Seq Scan on pred_tab t2 -> Materialize -> Seq Scan on pred_tab t3 -(9 rows) +(12 rows) -- Ensure the IS_NULL qual is reduced to constant-FALSE, since a) it's on a NOT -- NULL column, and b) its Var is not nullable by any outer joins EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON t2.a IS NULL AND t2.b = 1; - QUERY PLAN ---------------------------------------------------- + LEFT JOIN pred_tab t2 ON t1.a IS NULL; + QUERY PLAN +-------------------------------- Nested Loop Left Join + Join Filter: false -> Seq Scan on pred_tab t1 - -> Materialize - -> Nested Loop Left Join - Join Filter: (false AND (t2.b = 1)) - -> Seq Scan on pred_tab t2 - -> Result - One-Time Filter: false -(8 rows) + -> Result + One-Time Filter: false +(5 rows) -- Ensure the IS_NULL qual is not reduced to constant-FALSE when the column is -- nullable by an outer join @@ -172,55 +167,50 @@ SELECT * FROM pred_tab t1 -- Ensure the OR clause is ignored when an OR branch is provably always true EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL OR t2.b = 1; - QUERY PLAN -------------------------------------------------- + LEFT JOIN pred_tab t2 ON t1.a IS NOT NULL OR t2.b = 1; + QUERY PLAN +------------------------------------- Nested Loop Left Join -> Seq Scan on pred_tab t1 -> Materialize - -> Nested Loop Left Join - -> Seq Scan on pred_tab t2 - -> Materialize - -> Seq Scan on pred_tab t3 -(7 rows) + -> Seq Scan on pred_tab t2 +(4 rows) -- Ensure the NullTest is not ignored when the column is nullable by an outer -- join EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON t1.a = 1 + FULL JOIN pred_tab t2 ON t1.a = t2.a LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL OR t2.b = 1; QUERY PLAN --------------------------------------------------- Nested Loop Left Join Join Filter: ((t2.a IS NOT NULL) OR (t2.b = 1)) - -> Nested Loop Left Join - Join Filter: (t1.a = 1) - -> Seq Scan on pred_tab t1 - -> Materialize + -> Merge Full Join + Merge Cond: (t1.a = t2.a) + -> Sort + Sort Key: t1.a + -> Seq Scan on pred_tab t1 + -> Sort + Sort Key: t2.a -> Seq Scan on pred_tab t2 -> Materialize -> Seq Scan on pred_tab t3 -(9 rows) +(12 rows) -- Ensure the OR clause is reduced to constant-FALSE when all OR branches are -- provably false EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON (t2.a IS NULL OR t2.c IS NULL) AND t2.b = 1; - QUERY PLAN ---------------------------------------------------- + LEFT JOIN pred_tab t2 ON (t1.a IS NULL OR t1.c IS NULL); + QUERY PLAN +-------------------------------- Nested Loop Left Join + Join Filter: false -> Seq Scan on pred_tab t1 - -> Materialize - -> Nested Loop Left Join - Join Filter: (false AND (t2.b = 1)) - -> Seq Scan on pred_tab t2 - -> Result - One-Time Filter: false -(8 rows) + -> Result + One-Time Filter: false +(5 rows) -- Ensure the OR clause is not reduced to constant-FALSE when a column is -- made nullable from an outer join @@ -290,31 +280,84 @@ SELECT * FROM pred_parent WHERE a IS NULL; (2 rows) DROP TABLE pred_parent, pred_child; --- Validate the additional constant-FALSE qual does not cause inconsistent --- RestrictInfo serial numbers -CREATE TABLE pred_tab (a int PRIMARY KEY, b int); -INSERT INTO pred_tab SELECT i, i FROM generate_series(1, 10)i; +-- Validate we do not reduce a clone clause to a constant true or false +CREATE TABLE pred_tab (a int, b int); +CREATE TABLE pred_tab_notnull (a int, b int NOT NULL); +INSERT INTO pred_tab VALUES (1, 1); +INSERT INTO pred_tab VALUES (2, 2); +INSERT INTO pred_tab_notnull VALUES (2, 2); +INSERT INTO pred_tab_notnull VALUES (3, 3); ANALYZE pred_tab; +ANALYZE pred_tab_notnull; +-- Ensure the IS_NOT_NULL qual is not reduced to constant true and removed EXPLAIN (COSTS OFF) -SELECT 1 FROM pred_tab t1 - LEFT JOIN - (pred_tab t2 LEFT JOIN pred_tab t3 ON t2.a = t3.a) ON TRUE - LEFT JOIN pred_tab t4 ON t1.a IS NULL AND t1.b = 1 - RIGHT JOIN pred_tab t5 ON t1.b = t5.b; - QUERY PLAN ---------------------------------------------------- - Hash Right Join - Hash Cond: (t1.b = t5.b) - -> Nested Loop Left Join +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NOT NULL; + QUERY PLAN +--------------------------------------------------------------- + Nested Loop Left Join + -> Seq Scan on pred_tab t1 + -> Materialize -> Nested Loop Left Join - Join Filter: (false AND (t1.b = 1)) - -> Seq Scan on pred_tab t1 - -> Result - One-Time Filter: false - -> Materialize - -> Seq Scan on pred_tab t2 - -> Hash - -> Seq Scan on pred_tab t5 + Join Filter: (t3.b IS NOT NULL) + -> Nested Loop Left Join + Join Filter: (t2.a = t3.a) + -> Seq Scan on pred_tab t2 + -> Materialize + -> Seq Scan on pred_tab_notnull t3 + -> Materialize + -> Seq Scan on pred_tab t4 (12 rows) +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NOT NULL; + a | b | a | b | a | b | a | b +---+---+---+---+---+---+---+--- + 1 | 1 | 1 | 1 | | | | + 1 | 1 | 2 | 2 | 2 | 2 | 1 | 1 + 1 | 1 | 2 | 2 | 2 | 2 | 2 | 2 + 2 | 2 | 1 | 1 | | | | + 2 | 2 | 2 | 2 | 2 | 2 | 1 | 1 + 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 +(6 rows) + +-- Ensure the IS_NULL qual is not reduced to constant false +EXPLAIN (COSTS OFF) +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NULL AND t3.a IS NOT NULL; + QUERY PLAN +-------------------------------------------------------------------- + Nested Loop Left Join + -> Seq Scan on pred_tab t1 + -> Materialize + -> Nested Loop Left Join + Join Filter: ((t3.b IS NULL) AND (t3.a IS NOT NULL)) + -> Nested Loop Left Join + Join Filter: (t2.a = t3.a) + -> Seq Scan on pred_tab t2 + -> Materialize + -> Seq Scan on pred_tab_notnull t3 + -> Materialize + -> Seq Scan on pred_tab t4 +(12 rows) + +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NULL AND t3.a IS NOT NULL; + a | b | a | b | a | b | a | b +---+---+---+---+---+---+---+--- + 1 | 1 | 1 | 1 | | | | + 1 | 1 | 2 | 2 | 2 | 2 | | + 2 | 2 | 1 | 1 | | | | + 2 | 2 | 2 | 2 | 2 | 2 | | +(4 rows) + DROP TABLE pred_tab; +DROP TABLE pred_tab_notnull; diff --git a/src/test/regress/sql/predicate.sql b/src/test/regress/sql/predicate.sql index 661013ff7e4..9dcb81b1bc5 100644 --- a/src/test/regress/sql/predicate.sql +++ b/src/test/regress/sql/predicate.sql @@ -64,22 +64,20 @@ SELECT * FROM pred_tab t WHERE t.b IS NULL OR t.c IS NULL; -- and b) its Var is not nullable by any outer joins EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL; + LEFT JOIN pred_tab t2 ON t1.a IS NOT NULL; -- Ensure the IS_NOT_NULL qual is not ignored when columns are made nullable -- by an outer join EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON t1.a = 1 + FULL JOIN pred_tab t2 ON t1.a = t2.a LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL; -- Ensure the IS_NULL qual is reduced to constant-FALSE, since a) it's on a NOT -- NULL column, and b) its Var is not nullable by any outer joins EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON t2.a IS NULL AND t2.b = 1; + LEFT JOIN pred_tab t2 ON t1.a IS NULL; -- Ensure the IS_NULL qual is not reduced to constant-FALSE when the column is -- nullable by an outer join @@ -95,22 +93,20 @@ SELECT * FROM pred_tab t1 -- Ensure the OR clause is ignored when an OR branch is provably always true EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL OR t2.b = 1; + LEFT JOIN pred_tab t2 ON t1.a IS NOT NULL OR t2.b = 1; -- Ensure the NullTest is not ignored when the column is nullable by an outer -- join EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON t1.a = 1 + FULL JOIN pred_tab t2 ON t1.a = t2.a LEFT JOIN pred_tab t3 ON t2.a IS NOT NULL OR t2.b = 1; -- Ensure the OR clause is reduced to constant-FALSE when all OR branches are -- provably false EXPLAIN (COSTS OFF) SELECT * FROM pred_tab t1 - LEFT JOIN pred_tab t2 ON TRUE - LEFT JOIN pred_tab t3 ON (t2.a IS NULL OR t2.c IS NULL) AND t2.b = 1; + LEFT JOIN pred_tab t2 ON (t1.a IS NULL OR t1.c IS NULL); -- Ensure the OR clause is not reduced to constant-FALSE when a column is -- made nullable from an outer join @@ -148,17 +144,42 @@ SELECT * FROM pred_parent WHERE a IS NULL; DROP TABLE pred_parent, pred_child; --- Validate the additional constant-FALSE qual does not cause inconsistent --- RestrictInfo serial numbers -CREATE TABLE pred_tab (a int PRIMARY KEY, b int); -INSERT INTO pred_tab SELECT i, i FROM generate_series(1, 10)i; -ANALYZE pred_tab; +-- Validate we do not reduce a clone clause to a constant true or false +CREATE TABLE pred_tab (a int, b int); +CREATE TABLE pred_tab_notnull (a int, b int NOT NULL); +INSERT INTO pred_tab VALUES (1, 1); +INSERT INTO pred_tab VALUES (2, 2); + +INSERT INTO pred_tab_notnull VALUES (2, 2); +INSERT INTO pred_tab_notnull VALUES (3, 3); + +ANALYZE pred_tab; +ANALYZE pred_tab_notnull; + +-- Ensure the IS_NOT_NULL qual is not reduced to constant true and removed EXPLAIN (COSTS OFF) -SELECT 1 FROM pred_tab t1 - LEFT JOIN - (pred_tab t2 LEFT JOIN pred_tab t3 ON t2.a = t3.a) ON TRUE - LEFT JOIN pred_tab t4 ON t1.a IS NULL AND t1.b = 1 - RIGHT JOIN pred_tab t5 ON t1.b = t5.b; +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NOT NULL; + +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NOT NULL; + +-- Ensure the IS_NULL qual is not reduced to constant false +EXPLAIN (COSTS OFF) +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NULL AND t3.a IS NOT NULL; + +SELECT * FROM pred_tab t1 + LEFT JOIN pred_tab t2 ON TRUE + LEFT JOIN pred_tab_notnull t3 ON t2.a = t3.a + LEFT JOIN pred_tab t4 ON t3.b IS NULL AND t3.a IS NOT NULL; DROP TABLE pred_tab; +DROP TABLE pred_tab_notnull;