diff options
| author | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2022-03-28 16:45:58 +0200 |
|---|---|---|
| committer | Alvaro Herrera <alvherre@alvh.no-ip.org> | 2022-03-28 16:47:48 +0200 |
| commit | 7103ebb7aae8ab8076b7e85f335ceb8fe799097c (patch) | |
| tree | 0bc2faf176b58d2546de40c3c36d93a4cdf1aafe /src/backend/catalog/sql_features.txt | |
| parent | ae63017bdb316b16a9f201b10f1221598111d6c5 (diff) | |
Add support for MERGE SQL command
MERGE performs actions that modify rows in the target table using a
source table or query. MERGE provides a single SQL statement that can
conditionally INSERT/UPDATE/DELETE rows -- a task that would otherwise
require multiple PL statements. For example,
MERGE INTO target AS t
USING source AS s
ON t.tid = s.sid
WHEN MATCHED AND t.balance > s.delta THEN
UPDATE SET balance = t.balance - s.delta
WHEN MATCHED THEN
DELETE
WHEN NOT MATCHED AND s.delta > 0 THEN
INSERT VALUES (s.sid, s.delta)
WHEN NOT MATCHED THEN
DO NOTHING;
MERGE works with regular tables, partitioned tables and inheritance
hierarchies, including column and row security enforcement, as well as
support for row and statement triggers and transition tables therein.
MERGE is optimized for OLTP and is parameterizable, though also useful
for large scale ETL/ELT. MERGE is not intended to be used in preference
to existing single SQL commands for INSERT, UPDATE or DELETE since there
is some overhead. MERGE can be used from PL/pgSQL.
MERGE does not support targetting updatable views or foreign tables, and
RETURNING clauses are not allowed either. These limitations are likely
fixable with sufficient effort. Rewrite rules are also not supported,
but it's not clear that we'd want to support them.
Author: Pavan Deolasee <pavan.deolasee@gmail.com>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Author: Amit Langote <amitlangote09@gmail.com>
Author: Simon Riggs <simon.riggs@enterprisedb.com>
Reviewed-by: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Reviewed-by: Andres Freund <andres@anarazel.de> (earlier versions)
Reviewed-by: Peter Geoghegan <pg@bowt.ie> (earlier versions)
Reviewed-by: Robert Haas <robertmhaas@gmail.com> (earlier versions)
Reviewed-by: Japin Li <japinli@hotmail.com>
Reviewed-by: Justin Pryzby <pryzby@telsasoft.com>
Reviewed-by: Tomas Vondra <tomas.vondra@enterprisedb.com>
Reviewed-by: Zhihong Yu <zyu@yugabyte.com>
Discussion: https://postgr.es/m/CANP8+jKitBSrB7oTgT9CY2i1ObfOt36z0XMraQc+Xrz8QB0nXA@mail.gmail.com
Discussion: https://postgr.es/m/CAH2-WzkJdBuxj9PO=2QaO9-3h3xGbQPZ34kJH=HukRekwM-GZg@mail.gmail.com
Discussion: https://postgr.es/m/20201231134736.GA25392@alvherre.pgsql
Diffstat (limited to 'src/backend/catalog/sql_features.txt')
| -rw-r--r-- | src/backend/catalog/sql_features.txt | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/src/backend/catalog/sql_features.txt b/src/backend/catalog/sql_features.txt index 097d9c4784b..4c3e29111de 100644 --- a/src/backend/catalog/sql_features.txt +++ b/src/backend/catalog/sql_features.txt @@ -240,9 +240,9 @@ F311 Schema definition statement 02 CREATE TABLE for persistent base tables YES F311 Schema definition statement 03 CREATE VIEW YES F311 Schema definition statement 04 CREATE VIEW: WITH CHECK OPTION YES F311 Schema definition statement 05 GRANT statement YES -F312 MERGE statement NO consider INSERT ... ON CONFLICT DO UPDATE -F313 Enhanced MERGE statement NO -F314 MERGE statement with DELETE branch NO +F312 MERGE statement YES +F313 Enhanced MERGE statement YES +F314 MERGE statement with DELETE branch YES F321 User authorization YES F341 Usage tables YES F361 Subprogram support YES |