Source: https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/data-admin/show/show-user-defined-functions/
Documentation version: v5.3.2

# SHOW USER DEFINED FUNCTION / FUNCTIONS command

The SHOW USER DEFINED FUNCTIONS command displays all user-defined functions (UDFs) in the current schema. The `SHOW USER DEFINED FUNCTION <function_name>` command displays the UDFs that match the specified function name.

If the current user does not have `USAGE` on the current schema, no UDFs in that schema are returned. For more information, see [Schema access control](https://dev-docs.nebula-graph.io/v5.3.2/server-admin/authorization/schema-access-control/).

The following table describes the returned information:

 | Column | Description
 | `name` | The name of the UDF.
 | `signature` | The signature of the UDF.
 | `comment` | The description of the UDF.

To view additional columns including the UDF `category` and `null_behavior`, use the `VERBOSE` option. See [Syntax](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/data-admin/show/show-user-defined-functions/#syntax).

When the `VERBOSE` option is used, the following additional columns are returned:

 | Column | Description
 | `category` | The category of the UDF.
 | `null_behavior` | The NULL handling behavior of the UDF.

## Syntax

diagramsource

 show_udf_statement show_specific_udf_statement  

````
show_udf_statement ::= 
    'SHOW' 'GQL'? 'USER DEFINED' 'FUNCTIONS' 'VERBOSE'?

show_specific_udf_statement ::= 
    'SHOW' 'GQL'? 'USER DEFINED' 'FUNCTION' function_name 'VERBOSE'?

````

- `VERBOSE`: If specified, the output includes the additional `category` and `null_behavior` columns.

## Parameters

### `function_name`

The name of the UDF for which to display information.

You can specify a regular expression to match multiple UDFs. The regular expression must be enclosed in double quotes (`"`) or backticks (```). For example, `SHOW USER DEFINED FUNCTION "add_.*"` matches all UDFs whose names start with `add_`.

To view all UDFs, use the `SHOW USER DEFINED FUNCTIONS` command.

## Examples

The following examples are based on the UDFs created in [User-defined functions](https://dev-docs.nebula-graph.io/v5.3.2/database-gql-reference/fe/functions/user-defined/).

### Show all UDFs

````
SHOW USER DEFINED FUNCTIONS

````

Return:

````
+------------+----------------------------------------------------+------------------------------------+
| name       | signature                                          | comment                            |
+------------+----------------------------------------------------+------------------------------------+
| _pi        | _pi() -> FLOAT { 3.1415926 }                       |                                    |
| add_offset | add_offset(x FLOAT) -> FLOAT { x + $offset }       |                                    |
| add_tax    | add_tax(price FLOAT) -> FLOAT { price * 1.06 }     | Calculates the price including tax |
| avg_sum    | avg_sum(b FLOAT) -> FLOAT { avg(b) + sum(abs(b)) } |                                    |
| foo        | foo(a INT64, b FLOAT) -> FLOAT { a + b }           |                                    |
+------------+----------------------------------------------------+------------------------------------+

````

### Show UDFs matching the specified function name

````
SHOW USER DEFINED FUNCTION foo

````

Return:

````
+------+------------------------------------------+---------+
| name | signature                                | comment |
+------+------------------------------------------+---------+
| foo  | foo(a INT64, b FLOAT) -> FLOAT { a + b } |         |
+------+------------------------------------------+---------+

````

### Show UDFs matching the specified regular expression

````
SHOW USER DEFINED FUNCTION "add_.*"

````

Return:

````
+------------+----------------------------------------------+---------+
| name       | signature                                    | comment |
+------------+----------------------------------------------+---------+
| add_offset | add_offset(x FLOAT) -> FLOAT { x + $offset } |         |
+------------+----------------------------------------------+---------+

````