From 25fad5800d1f0054effa49e86c081306d9bee7fa Mon Sep 17 00:00:00 2001 From: Gareth Palmer Date: Fri, 16 Aug 2019 11:56:42 +1200 Subject: [PATCH] Implement INSERT SET syntax Allow the target column and values of an INSERT statement to be specified using a SET clause in the same manner as that of an UPDATE statement. The advantage of using the INSERT SET style is that the columns and values are kept together, which can make changing or removing a column or value from a large list easier. A simple example that uses SET instead of a VALUES() clause: INSERT INTO t SET c1 = 'foo', c2 = 'bar', c3 = 'baz'; Values may also be sourced from a CTE using a FROM clause: WITH x AS ( SELECT 'foo' AS c1, 'bar' AS c2, 'baz' AS c3 ) INSERT INTO t SET c1 = x.c1, c2 = x.c2, c3 = x.c3 FROM x; INSERT SET is not part of any SQL standard, however this syntax is also implemented by MySQL. Their implementation does not support specifying a FROM clause. --- doc/src/sgml/ref/insert.sgml | 24 ++++++++++- src/backend/parser/gram.y | 40 ++++++++++++++++++- src/backend/parser/parse_expr.c | 8 +++- src/test/regress/expected/insert.out | 16 ++++++++ src/test/regress/expected/insert_conflict.out | 2 + src/test/regress/expected/with.out | 21 ++++++++++ src/test/regress/sql/insert.sql | 12 ++++++ src/test/regress/sql/insert_conflict.sql | 3 ++ src/test/regress/sql/with.sql | 10 +++++ 9 files changed, 132 insertions(+), 4 deletions(-) diff --git a/doc/src/sgml/ref/insert.sgml b/doc/src/sgml/ref/insert.sgml index f995a7637f..341616d8b5 100644 --- a/doc/src/sgml/ref/insert.sgml +++ b/doc/src/sgml/ref/insert.sgml @@ -24,7 +24,12 @@ PostgreSQL documentation [ WITH [ RECURSIVE ] with_query [, ...] ] INSERT INTO table_name [ AS alias ] [ ( column_name [, ...] ) ] [ OVERRIDING { SYSTEM | USER} VALUE ] - { DEFAULT VALUES | VALUES ( { expression | DEFAULT } [, ...] ) [, ...] | query } + { DEFAULT VALUES | VALUES ( { expression | DEFAULT } [, ...] ) [, ...] | + SET { column_name = { expression | DEFAULT } | + ( column_name [, ...] ) = [ ROW ] ( { expression | DEFAULT } [, ...] ) | + ( column_name [, ...] ) = ( sub-SELECT ) + } [, ...] [ FROM from_list ] } | + query } [ ON CONFLICT [ conflict_target ] conflict_action ] [ RETURNING * | output_expression [ [ AS ] output_name ] [, ...] ] @@ -254,6 +259,16 @@ INSERT INTO table_name [ AS + + from_list + + + A list of table expressions, allowing columns from other tables + to be used as values in the expression. + + + + DEFAULT @@ -675,6 +690,13 @@ WITH upd AS ( RETURNING * ) INSERT INTO employees_log SELECT *, current_timestamp FROM upd; + + + + Insert a single row into table distributors using a +SET clause to specify the columns and values: + +INSERT INTO distributors SET did = 4, dname = 'Hammers Unlimited, LLC'; diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index c97bb367f8..3015a2925a 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -463,7 +463,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query); %type OptSeqOptList SeqOptList OptParenthesizedSeqOptList %type SeqOptElem -%type insert_rest +%type insert_rest insert_set_clause %type opt_conf_expr %type opt_on_conflict @@ -10892,6 +10892,15 @@ insert_rest: $$->override = $5; $$->selectStmt = $7; } + | insert_set_clause + { + $$ = $1; + } + | OVERRIDING override_kind VALUE_P insert_set_clause + { + $$ = $4; + $$->override = $2; + } | DEFAULT VALUES { $$ = makeNode(InsertStmt); @@ -10923,6 +10932,35 @@ insert_column_item: } ; +insert_set_clause: + SET set_clause_list from_clause + { + SelectStmt *n = makeNode(SelectStmt); + + if ($3 != NULL) + { + n->targetList = $2; + n->fromClause = $3; + } + else + { + List *values = NIL; + ListCell *col_cell; + + foreach(col_cell, $2) + { + ResTarget *res_col = (ResTarget *) lfirst(col_cell); + + values = lappend(values, res_col->val); + } + n->valuesLists = list_make1(values); + } + $$ = makeNode(InsertStmt); + $$->cols = $2; + $$->selectStmt = (Node *) n; + } + ; + opt_on_conflict: ON CONFLICT opt_conf_expr DO UPDATE SET set_clause_list where_clause { diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c index 76f3dd7076..63ef879447 100644 --- a/src/backend/parser/parse_expr.c +++ b/src/backend/parser/parse_expr.c @@ -1566,8 +1566,12 @@ transformMultiAssignRef(ParseState *pstate, MultiAssignRef *maref) Query *qtree; TargetEntry *tle; - /* We should only see this in first-stage processing of UPDATE tlists */ - Assert(pstate->p_expr_kind == EXPR_KIND_UPDATE_SOURCE); + /* + * We should only see this in first-stage processing of UPDATE tlists + * or of an INSERT SET tlist. + */ + Assert(pstate->p_expr_kind == EXPR_KIND_UPDATE_SOURCE || + pstate->p_expr_kind == EXPR_KIND_VALUES_SINGLE); /* We only need to transform the source if this is the first column */ if (maref->colno == 1) diff --git a/src/test/regress/expected/insert.out b/src/test/regress/expected/insert.out index 75e25cdf48..c15260ea76 100644 --- a/src/test/regress/expected/insert.out +++ b/src/test/regress/expected/insert.out @@ -80,6 +80,22 @@ select col1, col2, char_length(col3) from inserttest; 30 | 50 | 10000 (8 rows) +drop table inserttest; +-- +-- SET test +-- +create table inserttest (col1 int4, col2 text default 'bar'); +insert into inserttest set col1 = 1, col2 = 'foo'; +insert into inserttest set col1 = 2, col2 = DEFAULT; +insert into inserttest set (col1, col2) = (3, 'baz'); +select * from inserttest; + col1 | col2 +------+------ + 1 | foo + 2 | bar + 3 | baz +(3 rows) + drop table inserttest; -- -- check indirection (field/array assignment), cf bug #14265 diff --git a/src/test/regress/expected/insert_conflict.out b/src/test/regress/expected/insert_conflict.out index 1338b2b23e..4d6538b1fb 100644 --- a/src/test/regress/expected/insert_conflict.out +++ b/src/test/regress/expected/insert_conflict.out @@ -236,6 +236,8 @@ insert into insertconflicttest values (2, 'Orange') on conflict (key, key, key) insert into insertconflicttest values (1, 'Apple'), (2, 'Orange') on conflict (key) do update set (fruit, key) = (excluded.fruit, excluded.key); +-- Using insert set syntax +insert into insertconflicttest set key = 1, fruit = 'Banana' on conflict (key) do update set fruit = excluded.fruit; -- Give good diagnostic message when EXCLUDED.* spuriously referenced from -- RETURNING: insert into insertconflicttest values (1, 'Apple') on conflict (key) do update set fruit = excluded.fruit RETURNING excluded.fruit; diff --git a/src/test/regress/expected/with.out b/src/test/regress/expected/with.out index 2a2085556b..b92f9f8a13 100644 --- a/src/test/regress/expected/with.out +++ b/src/test/regress/expected/with.out @@ -952,6 +952,27 @@ SELECT * FROM y; 10 (10 rows) +DROP TABLE y; +CREATE TEMPORARY TABLE y (a INTEGER); +WITH t AS ( + SELECT generate_series(1, 10) AS a +) +INSERT INTO y SET a = t.a+20 FROM t; +SELECT * FROM y; + a +---- + 21 + 22 + 23 + 24 + 25 + 26 + 27 + 28 + 29 + 30 +(10 rows) + DROP TABLE y; -- -- error cases diff --git a/src/test/regress/sql/insert.sql b/src/test/regress/sql/insert.sql index 23885f638c..00747e0939 100644 --- a/src/test/regress/sql/insert.sql +++ b/src/test/regress/sql/insert.sql @@ -37,6 +37,18 @@ select col1, col2, char_length(col3) from inserttest; drop table inserttest; +-- +-- SET test +-- +create table inserttest (col1 int4, col2 text default 'bar'); +insert into inserttest set col1 = 1, col2 = 'foo'; +insert into inserttest set col1 = 2, col2 = DEFAULT; +insert into inserttest set (col1, col2) = (3, 'baz'); + +select * from inserttest; + +drop table inserttest; + -- -- check indirection (field/array assignment), cf bug #14265 -- diff --git a/src/test/regress/sql/insert_conflict.sql b/src/test/regress/sql/insert_conflict.sql index 43691cd335..e0eb2df0c8 100644 --- a/src/test/regress/sql/insert_conflict.sql +++ b/src/test/regress/sql/insert_conflict.sql @@ -97,6 +97,9 @@ insert into insertconflicttest values (1, 'Apple'), (2, 'Orange') on conflict (key) do update set (fruit, key) = (excluded.fruit, excluded.key); +-- Using insert set syntax +insert into insertconflicttest set key = 1, fruit = 'Banana' on conflict (key) do update set fruit = excluded.fruit; + -- Give good diagnostic message when EXCLUDED.* spuriously referenced from -- RETURNING: insert into insertconflicttest values (1, 'Apple') on conflict (key) do update set fruit = excluded.fruit RETURNING excluded.fruit; diff --git a/src/test/regress/sql/with.sql b/src/test/regress/sql/with.sql index f85645efde..e6d2e13714 100644 --- a/src/test/regress/sql/with.sql +++ b/src/test/regress/sql/with.sql @@ -406,6 +406,16 @@ SELECT * FROM y; DROP TABLE y; +CREATE TEMPORARY TABLE y (a INTEGER); +WITH t AS ( + SELECT generate_series(1, 10) AS a +) +INSERT INTO y SET a = t.a+20 FROM t; + +SELECT * FROM y; + +DROP TABLE y; + -- -- error cases -- -- 2.17.1