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# DROP FUNCTION

## Synopsis <a href="#synopsis" id="synopsis"></a>

```sql
DROP FUNCTION function_name (arg_name arg_type [, ...]);
```

## Description

Drops an existing user-defined function. The function's name and its list of arguments (as specified when the function was created using the [CREATE FUNCTION](/reference/sql-syntax/ddl/create-function.md) statement) should be provided for identifying the function. Only the function owner can execute this statement.

{% hint style="warning" %}
**Important** `DROP FUNCTION` cannot be undone. Use it with care!
{% endhint %}

Functions display only if the current [Access Control](/overview/core-concepts/access-control.md#role) has `USAGE` privileges on them.

### Arguments

#### function\_name

The name of the function to drop. If the name is case-sensitive, you must wrap it in double quotes; otherwise, the system uses the lower case name.

#### (arg\_name arg\_type \[,…​])

An ordered list of function argument names and types.

## Example

#### Drop a function

Assume a user-defined function, named `touppercase`, is created using the [CREATE FUNCTION](/reference/sql-syntax/ddl/create-function.md) statement and is now available:

```sh
db1.public/my_store# CREATE FUNCTION toUpperCase (s VARCHAR) RETURNS VARCHAR LANGUAGE JAVA WITH ('source.name' = 'mysrc', 'class.name' = 'util.UpperCase');
+------------+-------------+------------+------------------------------------------+
|  Type      |  Name       |  Command   |  Summary                                 |
+============+=============+============+==========================================+
| function   | touppercase | CREATE     | function touppercase was successfully    |
|            |             |            | created                                  |
+------------+-------------+------------+------------------------------------------+
```

You can drop this function with the below statement:

```sh
db1.public/my_store# SHOW FUNCTIONS;
+--------------------------------+-------+--------------+----------------+--------------------+------------+-------------+-------------------------------+-------------------------------+
|  Signature                     |  Type |  Source Name |  Class Name    |  Egress Allow URIs |  Owner     |  Properties |  Created At                   |  Updated At                   |
+================================+=======+==============+================+====================+============+=============+===============================+===============================+
| touppercase(s VARCHAR) VARCHAR | udf   | functions    | util.UpperCase |                    | sysadmin   | {}          | 2024-07-02 22:25:20 +0000 UTC | 2024-07-02 22:25:20 +0000 UTC |
+--------------------------------+-------+--------------+----------------+--------------------+------------+-------------+-------------------------------+-------------------------------+
db1.public/my_store# DROP FUNCTION toUpperCase (s VARCHAR);
+------------+-------------+------------+---------------------------------------+
|  Type      |  Name       |  Command   |  Summary                              |
+============+=============+============+=======================================+
| function   | touppercase | DROP       | function touppercase has been deleted |
+------------+-------------+------------+---------------------------------------+
```