On Sun, Dec 1, 2019 at 4:32 PM Michael Paquier <mich...@paquier.xyz> wrote:
>
> On Fri, Nov 22, 2019 at 12:24:15PM +1300, Gareth Palmer wrote:
> > Attached is an updated patch with for_locking_clause added, test-cases
> > re-use existing tables and the comments and documentation have been
> > expanded.
>
> Per the automatic patch tester, documentation included in the patch
> does not build. Could you please fix that? I have moved the patch to
> next CF, waiting on author.
Attached is a fixed version.
> --
> Michael
From c7c32435f0c0a1948e5c3ebd7d66f0bc415ee54e Mon Sep 17 00:00:00 2001
From: Gareth Palmer <gar...@internetnz.net.nz>
Date: Mon, 2 Dec 2019 10:59:40 +0000
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 can also be sourced from other tables similar to the INSERT INTO
SELECT FROM syntax:
INSERT INTO t SET c1 = x.c1, c2 = x.c2 FROM x WHERE x.c2 > 10 LIMIT 10;
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 | 59 ++++++++++++++++++-
src/backend/parser/gram.y | 58 +++++++++++++++++-
src/backend/parser/parse_expr.c | 10 +++-
src/test/regress/expected/insert.out | 26 +++++---
src/test/regress/expected/insert_conflict.out | 2 +
src/test/regress/expected/with.out | 20 +++++++
src/test/regress/sql/insert.sql | 2 +
src/test/regress/sql/insert_conflict.sql | 3 +
src/test/regress/sql/with.sql | 9 +++
9 files changed, 177 insertions(+), 12 deletions(-)
diff --git a/doc/src/sgml/ref/insert.sgml b/doc/src/sgml/ref/insert.sgml
index e829c61642..b2f7c06f53 100644
--- a/doc/src/sgml/ref/insert.sgml
+++ b/doc/src/sgml/ref/insert.sgml
@@ -28,6 +28,19 @@ INSERT INTO <replaceable class="parameter">table_name</replaceable> [ AS <replac
[ ON CONFLICT [ <replaceable class="parameter">conflict_target</replaceable> ] <replaceable class="parameter">conflict_action</replaceable> ]
[ RETURNING * | <replaceable class="parameter">output_expression</replaceable> [ [ AS ] <replaceable class="parameter">output_name</replaceable> ] [, ...] ]
+
+[ WITH [ RECURSIVE ] <replaceable class="parameter">with_query</replaceable> [, ...] ]
+INSERT INTO <replaceable class="parameter">table_name</replaceable> [ AS <replaceable class="parameter">alias</replaceable> ]
+ [ OVERRIDING { SYSTEM | USER} VALUE ]
+ SET { <replaceable class="parameter">column_name</replaceable> = { <replaceable class="parameter">expression</replaceable> | DEFAULT } |
+ ( <replaceable class="parameter">column_name</replaceable> [, ...] ) = [ ROW ] ( { <replaceable class="parameter">expression</replaceable> | DEFAULT } [, ...] ) |
+ ( <replaceable class="parameter">column_name</replaceable> [, ...] ) = ( <replaceable class="parameter">sub-SELECT</replaceable> )
+ } [, ...]
+ [ FROM <replaceable class="parameter">from_clause</replaceable> ]
+ [ ON CONFLICT [ <replaceable class="parameter">conflict_target</replaceable> ] <replaceable class="parameter">conflict_action</replaceable> ]
+ [ RETURNING * | <replaceable class="parameter">output_expression</replaceable> [ [ AS ] <replaceable class="parameter">output_name</replaceable> ] [, ...] ]
+
+
<phrase>where <replaceable class="parameter">conflict_target</replaceable> can be one of:</phrase>
( { <replaceable class="parameter">index_column_name</replaceable> | ( <replaceable class="parameter">index_expression</replaceable> ) } [ COLLATE <replaceable class="parameter">collation</replaceable> ] [ <replaceable class="parameter">opclass</replaceable> ] [, ...] ) [ WHERE <replaceable class="parameter">index_predicate</replaceable> ]
@@ -254,6 +267,18 @@ INSERT INTO <replaceable class="parameter">table_name</replaceable> [ AS <replac
</listitem>
</varlistentry>
+ <varlistentry>
+ <term><replaceable class="parameter">from_clause</replaceable></term>
+ <listitem>
+ <para>
+ A list of table expressions, allowing columns from other tables
+ to be used as values in the <literal>expression</literal>.
+ Refer to the <xref linkend="sql-select"/> statement for a
+ description of the syntax.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry>
<term><literal>DEFAULT</literal></term>
<listitem>
@@ -631,6 +656,15 @@ INSERT INTO films (code, title, did, date_prod, kind) VALUES
</programlisting>
</para>
+ <para>
+ Insert a row using <command>SET</command> syntax:
+
+<programlisting>
+INSERT INTO films SET code = 'MH832', title = 'Blade Runner',
+ did = 201, date_prod = DEFAULT, kind = 'SciFi';
+</programlisting>
+ </para>
+
<para>
This example inserts some rows into table
<literal>films</literal> from a table <literal>tmp_films</literal>
@@ -677,6 +711,16 @@ WITH upd AS (
INSERT INTO employees_log SELECT *, current_timestamp FROM upd;
</programlisting>
</para>
+ <para>
+ Insert multiple rows into <literal>employees_log</literal> containing
+the hours worked by each employee from <literal>time_sheets</literal>.
+<programlisting>
+INSERT INTO employees_log SET id = time_sheets.employee,
+ total_hours = sum(time_sheets.hours) FROM time_sheets
+ WHERE time_sheets.date ≥ '2019-11-15' GROUP BY time_sheets.employee;
+</programlisting>
+ </para>
+
<para>
Insert or update new distributors as appropriate. Assumes a unique
index has been defined that constrains values appearing in the
@@ -733,6 +777,18 @@ INSERT INTO distributors (did, dname) VALUES (9, 'Antwerp Design')
INSERT INTO distributors (did, dname) VALUES (10, 'Conrad International')
ON CONFLICT (did) WHERE is_active DO NOTHING;
</programlisting></para>
+ <para>
+ Insert a new film into <literal>watched_films</literal> or increment the
+ number of times seen. Returns the new seen count, example assumes a
+ unique index has been defined that constrains the values appearing in
+ the <literal>title</literal> and <literal>year</literal> columns and
+ that <literal>seen_count</literal> defaults to 1.
+<programlisting>
+INSERT INTO watched_films SET title = 'Akira', year = 1988
+ ON CONFLICT (title, year) DO UPDATE SET seen_count = watched_films.seen_count + 1
+ RETURNING watched_films.seen_count;
+</programlisting>
+ </para>
</refsect1>
<refsect1>
@@ -743,7 +799,8 @@ INSERT INTO distributors (did, dname) VALUES (10, 'Conrad International')
the <literal>RETURNING</literal> clause is a
<productname>PostgreSQL</productname> extension, as is the ability
to use <literal>WITH</literal> with <command>INSERT</command>, and the ability to
- specify an alternative action with <literal>ON CONFLICT</literal>.
+ specify an alternative action with <literal>ON CONFLICT</literal>, and the
+ ability to specify the inserted columns using <literal>SET</literal>.
Also, the case in
which a column name list is omitted, but not all the columns are
filled from the <literal>VALUES</literal> clause or <replaceable>query</replaceable>,
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index c5086846de..dc825c64bc 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -465,7 +465,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%type <list> OptSeqOptList SeqOptList OptParenthesizedSeqOptList
%type <defelt> SeqOptElem
-%type <istmt> insert_rest
+%type <istmt> insert_rest insert_set_clause
%type <infer> opt_conf_expr
%type <onconflict> opt_on_conflict
@@ -10984,6 +10984,15 @@ 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);
@@ -11015,6 +11024,50 @@ insert_column_item:
}
;
+/*
+ * There are two rules here to handle the two different types of INSERT.
+ * INSERT using VALUES and INSERT using SELECT. They can't be combined
+ * because only the VALUES syntax allows specifying DEFAULT.
+ */
+insert_set_clause:
+ SET set_clause_list
+ {
+ SelectStmt *n = makeNode(SelectStmt);
+ 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;
+ $$->selectStmt = (Node *) n;
+ }
+ | SET set_clause_list FROM from_list where_clause group_clause
+ having_clause window_clause opt_sort_clause opt_select_limit
+ opt_for_locking_clause
+ {
+ SelectStmt *n = makeNode(SelectStmt);
+ n->targetList = $2;
+ n->fromClause = $4;
+ n->whereClause = $5;
+ n->groupClause = $6;
+ n->havingClause = $7;
+ n->windowClause = $8;
+ insertSelectOptions(n, $9, $11,
+ list_nth($10, 0), list_nth($10, 1),
+ NULL,
+ yyscanner);
+ $$ = makeNode(InsertStmt);
+ $$->cols = $2;
+ $$->selectStmt = (Node *) n;
+ }
+ ;
+
opt_on_conflict:
ON CONFLICT opt_conf_expr DO UPDATE SET set_clause_list where_clause
{
@@ -11398,6 +11451,9 @@ select_clause:
*
* NOTE: only the leftmost component SelectStmt should have INTO.
* However, this is not checked by the grammar; parse analysis must check it.
+ *
+ * NOTE: insert_set_clause also has SELECT-like syntax so if you add any
+ * clauses after from_clause here you may need to add them there as well.
*/
simple_select:
SELECT opt_all_clause opt_target_list
diff --git a/src/backend/parser/parse_expr.c b/src/backend/parser/parse_expr.c
index eb91da2d87..dc96ce76e4 100644
--- a/src/backend/parser/parse_expr.c
+++ b/src/backend/parser/parse_expr.c
@@ -1565,8 +1565,14 @@ 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
+ * (UPDATE_SOURCE), an INSERT SET tlist (VALUES_SINGLE) or from a rewritten
+ * query using rules (SELECT_TARGET).
+ */
+ Assert(pstate->p_expr_kind == EXPR_KIND_UPDATE_SOURCE ||
+ pstate->p_expr_kind == EXPR_KIND_VALUES_SINGLE ||
+ pstate->p_expr_kind == EXPR_KIND_SELECT_TARGET);
/* 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..1492ae40ee 100644
--- a/src/test/regress/expected/insert.out
+++ b/src/test/regress/expected/insert.out
@@ -9,14 +9,18 @@ insert into inserttest (col2, col3) values (3, DEFAULT);
insert into inserttest (col1, col2, col3) values (DEFAULT, 5, DEFAULT);
insert into inserttest values (DEFAULT, 5, 'test');
insert into inserttest values (DEFAULT, 7);
+insert into inserttest set col1 = DEFAULT, col2 = 9;
+insert into inserttest set (col1, col2, col3) = (DEFAULT, 11, 'more testing');
select * from inserttest;
- col1 | col2 | col3
-------+------+---------
+ col1 | col2 | col3
+------+------+--------------
| 3 | testing
| 5 | testing
| 5 | test
| 7 | testing
-(4 rows)
+ | 9 | testing
+ | 11 | more testing
+(6 rows)
--
-- insert with similar expression / target_list values (all fail)
@@ -38,13 +42,15 @@ ERROR: INSERT has more expressions than target columns
LINE 1: insert into inserttest (col1) values (DEFAULT, DEFAULT);
^
select * from inserttest;
- col1 | col2 | col3
-------+------+---------
+ col1 | col2 | col3
+------+------+--------------
| 3 | testing
| 5 | testing
| 5 | test
| 7 | testing
-(4 rows)
+ | 9 | testing
+ | 11 | more testing
+(6 rows)
--
-- VALUES test
@@ -58,10 +64,12 @@ select * from inserttest;
| 5 | testing
| 5 | test
| 7 | testing
+ | 9 | testing
+ | 11 | more testing
10 | 20 | 40
-1 | 2 | testing
2 | 3 | values are fun!
-(7 rows)
+(9 rows)
--
-- TOASTed value test
@@ -74,11 +82,13 @@ select col1, col2, char_length(col3) from inserttest;
| 5 | 7
| 5 | 4
| 7 | 7
+ | 9 | 7
+ | 11 | 12
10 | 20 | 2
-1 | 2 | 7
2 | 3 | 15
30 | 50 | 10000
-(8 rows)
+(10 rows)
drop table inserttest;
--
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..a1236d8683 100644
--- a/src/test/regress/expected/with.out
+++ b/src/test/regress/expected/with.out
@@ -952,6 +952,26 @@ SELECT * FROM y;
10
(10 rows)
+TRUNCATE TABLE y;
+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..bc903d3316 100644
--- a/src/test/regress/sql/insert.sql
+++ b/src/test/regress/sql/insert.sql
@@ -7,6 +7,8 @@ insert into inserttest (col2, col3) values (3, DEFAULT);
insert into inserttest (col1, col2, col3) values (DEFAULT, 5, DEFAULT);
insert into inserttest values (DEFAULT, 5, 'test');
insert into inserttest values (DEFAULT, 7);
+insert into inserttest set col1 = DEFAULT, col2 = 9;
+insert into inserttest set (col1, col2, col3) = (DEFAULT, 11, 'more testing');
select * from inserttest;
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..d3e04bbad9 100644
--- a/src/test/regress/sql/with.sql
+++ b/src/test/regress/sql/with.sql
@@ -404,6 +404,15 @@ DELETE FROM y USING t WHERE t.a = y.a RETURNING y.a;
SELECT * FROM y;
+TRUNCATE TABLE y;
+
+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;
--
--
2.17.1
