> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/reference/sql-commands/sql-alteraggregate.md).

# ALTER AGGREGATE

### ALTER AGGREGATE

ALTER AGGREGATE — change the definition of an aggregate function

### Synopsis

```

ALTER AGGREGATE name ( aggregate_signature ) RENAME TO new_name
ALTER AGGREGATE name ( aggregate_signature )
                OWNER TO { new_owner | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER AGGREGATE name ( aggregate_signature ) SET SCHEMA new_schema

where aggregate_signature is:

* |
[ argmode ] [ argname ] argtype [ , ... ] |
[ [ argmode ] [ argname ] argtype [ , ... ] ] ORDER BY [ argmode ] [ argname ] argtype [ , ... ]
```

### Description

`ALTER AGGREGATE` changes the definition of an aggregate function.

You must own the aggregate function to use `ALTER AGGREGATE`. To change the schema of an aggregate function, you must also have `CREATE` privilege on the new schema. To alter the owner, you must be able to `SET ROLE` to the new owning role, and that role must have `CREATE` privilege on the aggregate function's schema. (These restrictions enforce that altering the owner doesn't do anything you couldn't do by dropping and recreating the aggregate function. However, a superuser can alter ownership of any aggregate function anyway.)

### Parameters

*`name`* : The name (optionally schema-qualified) of an existing aggregate function.

*`argmode`* : The mode of an argument: `IN` or `VARIADIC`. If omitted, the default is `IN`.

*`argname`* : The name of an argument. Note that `ALTER AGGREGATE` does not actually pay any attention to argument names, since only the argument data types are needed to determine the aggregate function's identity.

*`argtype`* : An input data type on which the aggregate function operates. To reference a zero-argument aggregate function, write `*` in place of the list of argument specifications. To reference an ordered-set aggregate function, write `ORDER BY` between the direct and aggregated argument specifications.

*`new_name`* : The new name of the aggregate function.

*`new_owner`* : The new owner of the aggregate function.

*`new_schema`* : The new schema for the aggregate function.

### Notes

The recommended syntax for referencing an ordered-set aggregate is to write `ORDER BY` between the direct and aggregated argument specifications, in the same style as in [`CREATE AGGREGATE`](/reference/sql-commands/sql-createaggregate.md). However, it will also work to omit `ORDER BY` and just run the direct and aggregated argument specifications into a single list. In this abbreviated form, if `VARIADIC "any"` was used in both the direct and aggregated argument lists, write `VARIADIC "any"` only once.

### Examples

To rename the aggregate function `myavg` for type `integer` to `my_average`:

```

ALTER AGGREGATE myavg(integer) RENAME TO my_average;
```

To change the owner of the aggregate function `myavg` for type `integer` to `joe`:

```

ALTER AGGREGATE myavg(integer) OWNER TO joe;
```

To move the ordered-set aggregate `mypercentile` with direct argument of type `float8` and aggregated argument of type `integer` into schema `myschema`:

```

ALTER AGGREGATE mypercentile(float8 ORDER BY integer) SET SCHEMA myschema;
```

This will work too:

```

ALTER AGGREGATE mypercentile(float8, integer) SET SCHEMA myschema;
```

### Compatibility

There is no `ALTER AGGREGATE` statement in the SQL standard.

### See Also

[CREATE AGGREGATE](/reference/sql-commands/sql-createaggregate.md), [DROP AGGREGATE](/reference/sql-commands/sql-dropaggregate.md)

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/sql-alteraggregate.html)（英文原文，待翻譯）


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