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📄 ABORT.7(2.17 KB)
📄 ALTER_AGGREGATE.7(4.97 KB)
📄 ALTER_COLLATION.7(2.8 KB)
📄 ALTER_CONVERSION.7(2.89 KB)
📄 ALTER_DATABASE.7(5.71 KB)
📄 ALTER_DEFAULT_PRIVILEGES.7(6.34 KB)
📄 ALTER_DOMAIN.7(6.96 KB)
📄 ALTER_EVENT_TRIGGER.7(2.42 KB)
📄 ALTER_EXTENSION.7(6.89 KB)
📄 ALTER_FOREIGN_DATA_WRAPPER.7(4.56 KB)
📄 ALTER_FOREIGN_TABLE.7(12.8 KB)
📄 ALTER_FUNCTION.7(8.26 KB)
📄 ALTER_GROUP.7(3.08 KB)
📄 ALTER_INDEX.7(5.59 KB)
📄 ALTER_LANGUAGE.7(2.1 KB)
📄 ALTER_LARGE_OBJECT.7(1.97 KB)
📄 ALTER_MATERIALIZED_VIEW.7(4.66 KB)
📄 ALTER_OPERATOR.7(3.67 KB)
📄 ALTER_OPERATOR_CLASS.7(2.86 KB)
📄 ALTER_OPERATOR_FAMILY.7(9.12 KB)
📄 ALTER_POLICY.7(2.88 KB)
📄 ALTER_ROLE.7(9.04 KB)
📄 ALTER_RULE.7(2.21 KB)
📄 ALTER_SCHEMA.7(2.31 KB)
📄 ALTER_SEQUENCE.7(7.53 KB)
📄 ALTER_SERVER.7(3.41 KB)
📄 ALTER_SYSTEM.7(3.8 KB)
📄 ALTER_TABLE.7(35.2 KB)
📄 ALTER_TABLESPACE.7(3.35 KB)
📄 ALTER_TEXT_SEARCH_CONFIGURATION.7(4.79 KB)
📄 ALTER_TEXT_SEARCH_DICTIONARY.7(4.02 KB)
📄 ALTER_TEXT_SEARCH_PARSER.7(2.23 KB)
📄 ALTER_TEXT_SEARCH_TEMPLATE.7(2.26 KB)
📄 ALTER_TRIGGER.7(2.98 KB)
📄 ALTER_TYPE.7(7.15 KB)
📄 ALTER_USER.7(2.66 KB)
📄 ALTER_USER_MAPPING.7(3.26 KB)
📄 ALTER_VIEW.7(4.67 KB)
📄 ANALYZE.7(7.67 KB)
📄 BEGIN.7(4.06 KB)
📄 CHECKPOINT.7(2.29 KB)
📄 CLOSE.7(2.72 KB)
📄 CLUSTER.7(6.23 KB)
📄 COMMENT.7(10.2 KB)
📄 COMMIT.7(2.1 KB)
📄 COMMIT_PREPARED.7(2.58 KB)
📄 COPY.7(29.88 KB)
📄 CREATE_ACCESS_METHOD.7(2.9 KB)
📄 CREATE_AGGREGATE.7(23.35 KB)
📄 CREATE_CAST.7(13.55 KB)
📄 CREATE_COLLATION.7(3.97 KB)
📄 CREATE_CONVERSION.7(3.78 KB)
📄 CREATE_DATABASE.7(8.48 KB)
📄 CREATE_DOMAIN.7(6.52 KB)
📄 CREATE_EVENT_TRIGGER.7(3.74 KB)
📄 CREATE_EXTENSION.7(6.57 KB)
📄 CREATE_FOREIGN_DATA_WRAPPER.7(4.96 KB)
📄 CREATE_FOREIGN_TABLE.7(9 KB)
📄 CREATE_FUNCTION.7(24.73 KB)
📄 CREATE_GROUP.7(2.11 KB)
📄 CREATE_INDEX.7(19.56 KB)
📄 CREATE_LANGUAGE.7(9.83 KB)
📄 CREATE_MATERIALIZED_VIEW.7(4.21 KB)
📄 CREATE_OPERATOR.7(6.88 KB)
📄 CREATE_OPERATOR_CLASS.7(8.52 KB)
📄 CREATE_OPERATOR_FAMILY.7(3.6 KB)
📄 CREATE_POLICY.7(15.92 KB)
📄 CREATE_ROLE.7(12.69 KB)
📄 CREATE_RULE.7(8.63 KB)
📄 CREATE_SCHEMA.7(6.15 KB)
📄 CREATE_SEQUENCE.7(9.79 KB)
📄 CREATE_SERVER.7(3.63 KB)
📄 CREATE_TABLE.7(42.1 KB)
📄 CREATE_TABLESPACE.7(4.47 KB)
📄 CREATE_TABLE_AS.7(7.8 KB)
📄 CREATE_TEXT_SEARCH_CONFIGURATION.7(3.19 KB)
📄 CREATE_TEXT_SEARCH_DICTIONARY.7(3.34 KB)
📄 CREATE_TEXT_SEARCH_PARSER.7(3.56 KB)
📄 CREATE_TEXT_SEARCH_TEMPLATE.7(3.38 KB)
📄 CREATE_TRANSFORM.7(5.79 KB)
📄 CREATE_TRIGGER.7(16.3 KB)
📄 CREATE_TYPE.7(28.96 KB)
📄 CREATE_USER.7(2.45 KB)
📄 CREATE_USER_MAPPING.7(3.27 KB)
📄 CREATE_VIEW.7(14.63 KB)
📄 DEALLOCATE.7(1.98 KB)
📄 DECLARE.7(10.22 KB)
📄 DELETE.7(7.36 KB)
📄 DISCARD.7(2.81 KB)
📄 DO.7(3.08 KB)
📄 DROP_ACCESS_METHOD.7(2.35 KB)
📄 DROP_AGGREGATE.7(3.8 KB)
📄 DROP_CAST.7(2.26 KB)
📄 DROP_COLLATION.7(2.42 KB)
📄 DROP_CONVERSION.7(2.36 KB)
📄 DROP_DATABASE.7(2.38 KB)
📄 DROP_DOMAIN.7(2.34 KB)
📄 DROP_EVENT_TRIGGER.7(2.38 KB)
📄 DROP_EXTENSION.7(2.73 KB)
📄 DROP_FOREIGN_DATA_WRAPPER.7(2.61 KB)
📄 DROP_FOREIGN_TABLE.7(2.59 KB)
📄 DROP_FUNCTION.7(3.35 KB)
📄 DROP_GROUP.7(1.57 KB)
📄 DROP_INDEX.7(3.08 KB)
📄 DROP_LANGUAGE.7(2.86 KB)
📄 DROP_MATERIALIZED_VIEW.7(2.64 KB)
📄 DROP_OPERATOR.7(3.01 KB)
📄 DROP_OPERATOR_CLASS.7(3.48 KB)
📄 DROP_OPERATOR_FAMILY.7(3.24 KB)
📄 DROP_OWNED.7(3.14 KB)
📄 DROP_POLICY.7(2.53 KB)
📄 DROP_ROLE.7(3.05 KB)
📄 DROP_RULE.7(2.35 KB)
📄 DROP_SCHEMA.7(2.76 KB)
📄 DROP_SEQUENCE.7(2.46 KB)
📄 DROP_SERVER.7(2.39 KB)
📄 DROP_TABLE.7(2.97 KB)
📄 DROP_TABLESPACE.7(2.48 KB)
📄 DROP_TEXT_SEARCH_CONFIGURATION.7(2.83 KB)
📄 DROP_TEXT_SEARCH_DICTIONARY.7(2.75 KB)
📄 DROP_TEXT_SEARCH_PARSER.7(2.66 KB)
📄 DROP_TEXT_SEARCH_TEMPLATE.7(2.69 KB)
📄 DROP_TRANSFORM.7(2.59 KB)
📄 DROP_TRIGGER.7(2.6 KB)
📄 DROP_TYPE.7(2.53 KB)
📄 DROP_USER.7(1.65 KB)
📄 DROP_USER_MAPPING.7(2.56 KB)
📄 DROP_VIEW.7(2.43 KB)
📄 END.7(2.19 KB)
📄 EXECUTE.7(2.9 KB)
📄 EXPLAIN.7(13.03 KB)
📄 FETCH.7(8.48 KB)
📄 GRANT.7(21.29 KB)
📄 IMPORT_FOREIGN_SCHEMA.7(3.98 KB)
📄 INSERT.7(19.61 KB)
📄 LISTEN.7(3.51 KB)
📄 LOAD.7(2.54 KB)
📄 LOCK.7(8.01 KB)
📄 MOVE.7(2.92 KB)
📄 NOTIFY.7(8.21 KB)
📄 PREPARE.7(8.2 KB)
📄 PREPARE_TRANSACTION.7(5.74 KB)
📄 REASSIGN_OWNED.7(3.01 KB)
📄 REFRESH_MATERIALIZED_VIEW.7(3.92 KB)
📄 REINDEX.7(7.69 KB)
📄 RELEASE_SAVEPOINT.7(3 KB)
📄 RESET.7(2.93 KB)
📄 REVOKE.7(10.44 KB)
📄 ROLLBACK.7(2.09 KB)
📄 ROLLBACK_PREPARED.7(2.6 KB)
📄 ROLLBACK_TO_SAVEPOINT.7(3.94 KB)
📄 SAVEPOINT.7(3.5 KB)
📄 SECURITY_LABEL.7(5.39 KB)
📄 SELECT.7(63.33 KB)
📄 SELECT_INTO.7(4.37 KB)
📄 SET.7(7.57 KB)
📄 SET_CONSTRAINTS.7(4.48 KB)
📄 SET_ROLE.7(4.36 KB)
📄 SET_SESSION_AUTHORIZATION.7(3.88 KB)
📄 SET_TRANSACTION.7(8.27 KB)
📄 SHOW.7(4.22 KB)
📄 START_TRANSACTION.7(2.9 KB)
📄 TABLE.7(18 B)
📄 TRUNCATE.7(6.39 KB)
📄 UNLISTEN.7(2.75 KB)
📄 UPDATE.7(12.26 KB)
📄 VACUUM.7(7.92 KB)
📄 VALUES.7(6.94 KB)
📄 WITH.7(18 B)

Editing: UPDATE.7

'\" t
.\"     Title: UPDATE
.\"    Author: The PostgreSQL Global Development Group
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"      Date: 2018
.\"    Manual: PostgreSQL 9.6.9 Documentation
.\"    Source: PostgreSQL 9.6.9
.\"  Language: English
.\"
.TH "UPDATE" "7" "2018" "PostgreSQL 9.6.9" "PostgreSQL 9.6.9 Documentation"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el       .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
UPDATE \- update rows of a table
.SH "SYNOPSIS"
.sp
.nf
[ WITH [ RECURSIVE ] \fIwith_query\fR [, \&.\&.\&.] ]
UPDATE [ ONLY ] \fItable_name\fR [ * ] [ [ AS ] \fIalias\fR ]
    SET { \fIcolumn_name\fR = { \fIexpression\fR | DEFAULT } |
          ( \fIcolumn_name\fR [, \&.\&.\&.] ) = ( { \fIexpression\fR | DEFAULT } [, \&.\&.\&.] ) |
          ( \fIcolumn_name\fR [, \&.\&.\&.] ) = ( \fIsub\-SELECT\fR )
        } [, \&.\&.\&.]
    [ FROM \fIfrom_list\fR ]
    [ WHERE \fIcondition\fR | WHERE CURRENT OF \fIcursor_name\fR ]
    [ RETURNING * | \fIoutput_expression\fR [ [ AS ] \fIoutput_name\fR ] [, \&.\&.\&.] ]
.fi
.SH "DESCRIPTION"
.PP
\fBUPDATE\fR
changes the values of the specified columns in all rows that satisfy the condition\&. Only the columns to be modified need be mentioned in the
SET
clause; columns not explicitly modified retain their previous values\&.
.PP
There are two ways to modify a table using information contained in other tables in the database: using sub\-selects, or specifying additional tables in the
FROM
clause\&. Which technique is more appropriate depends on the specific circumstances\&.
.PP
The optional
RETURNING
clause causes
\fBUPDATE\fR
to compute and return value(s) based on each row actually updated\&. Any expression using the table\*(Aqs columns, and/or columns of other tables mentioned in
FROM, can be computed\&. The new (post\-update) values of the table\*(Aqs columns are used\&. The syntax of the
RETURNING
list is identical to that of the output list of
\fBSELECT\fR\&.
.PP
You must have the
UPDATE
privilege on the table, or at least on the column(s) that are listed to be updated\&. You must also have the
SELECT
privilege on any column whose values are read in the
\fIexpressions\fR
or
\fIcondition\fR\&.
.SH "PARAMETERS"
.PP
\fIwith_query\fR
.RS 4
The
WITH
clause allows you to specify one or more subqueries that can be referenced by name in the
\fBUPDATE\fR
query\&. See
Section 7.8, \(lqWITH Queries (Common Table Expressions)\(rq, in the documentation
and
\fBSELECT\fR(7)
for details\&.
.RE
.PP
\fItable_name\fR
.RS 4
The name (optionally schema\-qualified) of the table to update\&. If
ONLY
is specified before the table name, matching rows are updated in the named table only\&. If
ONLY
is not specified, matching rows are also updated in any tables inheriting from the named table\&. Optionally,
*
can be specified after the table name to explicitly indicate that descendant tables are included\&.
.RE
.PP
\fIalias\fR
.RS 4
A substitute name for the target table\&. When an alias is provided, it completely hides the actual name of the table\&. For example, given
UPDATE foo AS f, the remainder of the
\fBUPDATE\fR
statement must refer to this table as
f
not
foo\&.
.RE
.PP
\fIcolumn_name\fR
.RS 4
The name of a column in the table named by
\fItable_name\fR\&. The column name can be qualified with a subfield name or array subscript, if needed\&. Do not include the table\*(Aqs name in the specification of a target column \(em for example,
UPDATE table_name SET table_name\&.col = 1
is invalid\&.
.RE
.PP
\fIexpression\fR
.RS 4
An expression to assign to the column\&. The expression can use the old values of this and other columns in the table\&.
.RE
.PP
DEFAULT
.RS 4
Set the column to its default value (which will be NULL if no specific default expression has been assigned to it)\&.
.RE
.PP
\fIsub\-SELECT\fR
.RS 4
A
SELECT
sub\-query that produces as many output columns as are listed in the parenthesized column list preceding it\&. The sub\-query must yield no more than one row when executed\&. If it yields one row, its column values are assigned to the target columns; if it yields no rows, NULL values are assigned to the target columns\&. The sub\-query can refer to old values of the current row of the table being updated\&.
.RE
.PP
\fIfrom_list\fR
.RS 4
A list of table expressions, allowing columns from other tables to appear in the
WHERE
condition and the update expressions\&. This is similar to the list of tables that can be specified in the
FROM Clause
of a
\fBSELECT\fR
statement\&. Note that the target table must not appear in the
\fIfrom_list\fR, unless you intend a self\-join (in which case it must appear with an alias in the
\fIfrom_list\fR)\&.
.RE
.PP
\fIcondition\fR
.RS 4
An expression that returns a value of type
boolean\&. Only rows for which this expression returns
true
will be updated\&.
.RE
.PP
\fIcursor_name\fR
.RS 4
The name of the cursor to use in a
WHERE CURRENT OF
condition\&. The row to be updated is the one most recently fetched from this cursor\&. The cursor must be a non\-grouping query on the
\fBUPDATE\fR\*(Aqs target table\&. Note that
WHERE CURRENT OF
cannot be specified together with a Boolean condition\&. See
\fBDECLARE\fR(7)
for more information about using cursors with
WHERE CURRENT OF\&.
.RE
.PP
\fIoutput_expression\fR
.RS 4
An expression to be computed and returned by the
\fBUPDATE\fR
command after each row is updated\&. The expression can use any column names of the table named by
\fItable_name\fR
or table(s) listed in
FROM\&. Write
*
to return all columns\&.
.RE
.PP
\fIoutput_name\fR
.RS 4
A name to use for a returned column\&.
.RE
.SH "OUTPUTS"
.PP
On successful completion, an
\fBUPDATE\fR
command returns a command tag of the form
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE \fIcount\fR
.fi
.if n \{\
.RE
.\}
.sp
The
\fIcount\fR
is the number of rows updated, including matched rows whose values did not change\&. Note that the number may be less than the number of rows that matched the
\fIcondition\fR
when updates were suppressed by a
BEFORE UPDATE
trigger\&. If
\fIcount\fR
is 0, no rows were updated by the query (this is not considered an error)\&.
.PP
If the
\fBUPDATE\fR
command contains a
RETURNING
clause, the result will be similar to that of a
\fBSELECT\fR
statement containing the columns and values defined in the
RETURNING
list, computed over the row(s) updated by the command\&.
.SH "NOTES"
.PP
When a
FROM
clause is present, what essentially happens is that the target table is joined to the tables mentioned in the
\fIfrom_list\fR, and each output row of the join represents an update operation for the target table\&. When using
FROM
you should ensure that the join produces at most one output row for each row to be modified\&. In other words, a target row shouldn\*(Aqt join to more than one row from the other table(s)\&. If it does, then only one of the join rows will be used to update the target row, but which one will be used is not readily predictable\&.
.PP
Because of this indeterminacy, referencing other tables only within sub\-selects is safer, though often harder to read and slower than using a join\&.
.SH "EXAMPLES"
.PP
Change the word
Drama
to
Dramatic
in the column
kind
of the table
films:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE films SET kind = \*(AqDramatic\*(Aq WHERE kind = \*(AqDrama\*(Aq;
.fi
.if n \{\
.RE
.\}
.PP
Adjust temperature entries and reset precipitation to its default value in one row of the table
weather:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE weather SET temp_lo = temp_lo+1, temp_hi = temp_lo+15, prcp = DEFAULT
  WHERE city = \*(AqSan Francisco\*(Aq AND date = \*(Aq2003\-07\-03\*(Aq;
.fi
.if n \{\
.RE
.\}
.PP
Perform the same operation and return the updated entries:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE weather SET temp_lo = temp_lo+1, temp_hi = temp_lo+15, prcp = DEFAULT
  WHERE city = \*(AqSan Francisco\*(Aq AND date = \*(Aq2003\-07\-03\*(Aq
  RETURNING temp_lo, temp_hi, prcp;
.fi
.if n \{\
.RE
.\}
.PP
Use the alternative column\-list syntax to do the same update:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE weather SET (temp_lo, temp_hi, prcp) = (temp_lo+1, temp_lo+15, DEFAULT)
  WHERE city = \*(AqSan Francisco\*(Aq AND date = \*(Aq2003\-07\-03\*(Aq;
.fi
.if n \{\
.RE
.\}
.PP
Increment the sales count of the salesperson who manages the account for Acme Corporation, using the
FROM
clause syntax:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE employees SET sales_count = sales_count + 1 FROM accounts
  WHERE accounts\&.name = \*(AqAcme Corporation\*(Aq
  AND employees\&.id = accounts\&.sales_person;
.fi
.if n \{\
.RE
.\}
.PP
Perform the same operation, using a sub\-select in the
WHERE
clause:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE employees SET sales_count = sales_count + 1 WHERE id =
  (SELECT sales_person FROM accounts WHERE name = \*(AqAcme Corporation\*(Aq);
.fi
.if n \{\
.RE
.\}
.PP
Update contact names in an accounts table to match the currently assigned salesmen:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE accounts SET (contact_first_name, contact_last_name) =
    (SELECT first_name, last_name FROM salesmen
     WHERE salesmen\&.id = accounts\&.sales_id);
.fi
.if n \{\
.RE
.\}
.sp
A similar result could be accomplished with a join:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE accounts SET contact_first_name = first_name,
                    contact_last_name = last_name
  FROM salesmen WHERE salesmen\&.id = accounts\&.sales_id;
.fi
.if n \{\
.RE
.\}
.sp
However, the second query may give unexpected results if
salesmen\&.id
is not a unique key, whereas the first query is guaranteed to raise an error if there are multiple
id
matches\&. Also, if there is no match for a particular
accounts\&.sales_id
entry, the first query will set the corresponding name fields to NULL, whereas the second query will not update that row at all\&.
.PP
Update statistics in a summary table to match the current data:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE summary s SET (sum_x, sum_y, avg_x, avg_y) =
    (SELECT sum(x), sum(y), avg(x), avg(y) FROM data d
     WHERE d\&.group_id = s\&.group_id);
.fi
.if n \{\
.RE
.\}
.PP
Attempt to insert a new stock item along with the quantity of stock\&. If the item already exists, instead update the stock count of the existing item\&. To do this without failing the entire transaction, use savepoints:
.sp
.if n \{\
.RS 4
.\}
.nf
BEGIN;
\-\- other operations
SAVEPOINT sp1;
INSERT INTO wines VALUES(\*(AqChateau Lafite 2003\*(Aq, \*(Aq24\*(Aq);
\-\- Assume the above fails because of a unique key violation,
\-\- so now we issue these commands:
ROLLBACK TO sp1;
UPDATE wines SET stock = stock + 24 WHERE winename = \*(AqChateau Lafite 2003\*(Aq;
\-\- continue with other operations, and eventually
COMMIT;
.fi
.if n \{\
.RE
.\}
.PP
Change the
kind
column of the table
films
in the row on which the cursor
c_films
is currently positioned:
.sp
.if n \{\
.RS 4
.\}
.nf
UPDATE films SET kind = \*(AqDramatic\*(Aq WHERE CURRENT OF c_films;
.fi
.if n \{\
.RE
.\}
.SH "COMPATIBILITY"
.PP
This command conforms to the
SQL
standard, except that the
FROM
and
RETURNING
clauses are
PostgreSQL
extensions, as is the ability to use
WITH
with
\fBUPDATE\fR\&.
.PP
Some other database systems offer a
FROM
option in which the target table is supposed to be listed again within
FROM\&. That is not how
PostgreSQL
interprets
FROM\&. Be careful when porting applications that use this extension\&.
.PP
According to the standard, the source value for a parenthesized sub\-list of column names can be any row\-valued expression yielding the correct number of columns\&.
PostgreSQL
only allows the source value to be a parenthesized list of expressions or a sub\-SELECT\&. An individual column\*(Aqs updated value can be specified as
DEFAULT
in the list\-of\-expressions case, but not inside a sub\-SELECT\&.

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