# User-defined Function API
<a name="aws-glue-api-catalog-functions"></a>

The User-defined Function API describes AWS Glue data types and operations used in working with functions.

## Data types
<a name="aws-glue-api-catalog-functions-objects"></a>
+ [UserDefinedFunction structure](#aws-glue-api-catalog-functions-UserDefinedFunction)
+ [UserDefinedFunctionInput structure](#aws-glue-api-catalog-functions-UserDefinedFunctionInput)

## UserDefinedFunction structure
<a name="aws-glue-api-catalog-functions-UserDefinedFunction"></a>

Represents the equivalent of a Hive user-defined function (`UDF`) definition.

**Fields**
+ `FunctionName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the function.
+ `DatabaseName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the catalog database that contains the function.
+ `ClassName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The Java class that contains the function code.
+ `OwnerName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The owner of the function.
+ `OwnerType` – UTF-8 string (valid values: `USER` \$1 `ROLE` \$1 `GROUP`).

  The owner type.
+ `CreateTime` – Timestamp.

  The time at which the function was created.
+ `ResourceUris` – An array of [ResourceUri](aws-glue-api-common.md#aws-glue-api-common-ResourceUri) objects, not more than 1000 structures.

  The resource URIs for the function.
+ `CatalogId` – Catalog id string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The ID of the Data Catalog in which the function resides.

## UserDefinedFunctionInput structure
<a name="aws-glue-api-catalog-functions-UserDefinedFunctionInput"></a>

A structure used to create or update a user-defined function.

**Fields**
+ `FunctionName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the function.
+ `ClassName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The Java class that contains the function code.
+ `OwnerName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The owner of the function.
+ `OwnerType` – UTF-8 string (valid values: `USER` \$1 `ROLE` \$1 `GROUP`).

  The owner type.
+ `ResourceUris` – An array of [ResourceUri](aws-glue-api-common.md#aws-glue-api-common-ResourceUri) objects, not more than 1000 structures.

  The resource URIs for the function.

## Operations
<a name="aws-glue-api-catalog-functions-actions"></a>
+ [CreateUserDefinedFunction action (Python: create\$1user\$1defined\$1function)](#aws-glue-api-catalog-functions-CreateUserDefinedFunction)
+ [UpdateUserDefinedFunction action (Python: update\$1user\$1defined\$1function)](#aws-glue-api-catalog-functions-UpdateUserDefinedFunction)
+ [DeleteUserDefinedFunction action (Python: delete\$1user\$1defined\$1function)](#aws-glue-api-catalog-functions-DeleteUserDefinedFunction)
+ [GetUserDefinedFunction action (Python: get\$1user\$1defined\$1function)](#aws-glue-api-catalog-functions-GetUserDefinedFunction)
+ [GetUserDefinedFunctions action (Python: get\$1user\$1defined\$1functions)](#aws-glue-api-catalog-functions-GetUserDefinedFunctions)

## CreateUserDefinedFunction action (Python: create\$1user\$1defined\$1function)
<a name="aws-glue-api-catalog-functions-CreateUserDefinedFunction"></a>

Creates a new function definition in the Data Catalog.

**Request**
+ `CatalogId` – Catalog id string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The ID of the Data Catalog in which to create the function. If none is provided, the AWS account ID is used by default.
+ `DatabaseName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the catalog database in which to create the function.
+ `FunctionInput` – *Required:* An [UserDefinedFunctionInput](#aws-glue-api-catalog-functions-UserDefinedFunctionInput) object.

  A `FunctionInput` object that defines the function to create in the Data Catalog.

**Response**
+ *No Response parameters.*

**Errors**
+ `AlreadyExistsException`
+ `InvalidInputException`
+ `InternalServiceException`
+ `EntityNotFoundException`
+ `OperationTimeoutException`
+ `ResourceNumberLimitExceededException`
+ `GlueEncryptionException`

## UpdateUserDefinedFunction action (Python: update\$1user\$1defined\$1function)
<a name="aws-glue-api-catalog-functions-UpdateUserDefinedFunction"></a>

Updates an existing function definition in the Data Catalog.

**Request**
+ `CatalogId` – Catalog id string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The ID of the Data Catalog where the function to be updated is located. If none is provided, the AWS account ID is used by default.
+ `DatabaseName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the catalog database where the function to be updated is located.
+ `FunctionName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the function.
+ `FunctionInput` – *Required:* An [UserDefinedFunctionInput](#aws-glue-api-catalog-functions-UserDefinedFunctionInput) object.

  A `FunctionInput` object that redefines the function in the Data Catalog.

**Response**
+ *No Response parameters.*

**Errors**
+ `EntityNotFoundException`
+ `InvalidInputException`
+ `InternalServiceException`
+ `OperationTimeoutException`
+ `GlueEncryptionException`

## DeleteUserDefinedFunction action (Python: delete\$1user\$1defined\$1function)
<a name="aws-glue-api-catalog-functions-DeleteUserDefinedFunction"></a>

Deletes an existing function definition from the Data Catalog.

**Request**
+ `CatalogId` – Catalog id string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The ID of the Data Catalog where the function to be deleted is located. If none is supplied, the AWS account ID is used by default.
+ `DatabaseName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the catalog database where the function is located.
+ `FunctionName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the function definition to be deleted.

**Response**
+ *No Response parameters.*

**Errors**
+ `EntityNotFoundException`
+ `InvalidInputException`
+ `InternalServiceException`
+ `OperationTimeoutException`

## GetUserDefinedFunction action (Python: get\$1user\$1defined\$1function)
<a name="aws-glue-api-catalog-functions-GetUserDefinedFunction"></a>

Retrieves a specified function definition from the Data Catalog.

**Request**
+ `CatalogId` – Catalog id string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The ID of the Data Catalog where the function to be retrieved is located. If none is provided, the AWS account ID is used by default.
+ `DatabaseName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the catalog database where the function is located.
+ `FunctionName` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the function.

**Response**
+ `UserDefinedFunction` – An [UserDefinedFunction](#aws-glue-api-catalog-functions-UserDefinedFunction) object.

  The requested function definition.

**Errors**
+ `EntityNotFoundException`
+ `InvalidInputException`
+ `InternalServiceException`
+ `OperationTimeoutException`
+ `GlueEncryptionException`

## GetUserDefinedFunctions action (Python: get\$1user\$1defined\$1functions)
<a name="aws-glue-api-catalog-functions-GetUserDefinedFunctions"></a>

Retrieves multiple function definitions from the Data Catalog.

**Request**
+ `CatalogId` – Catalog id string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The ID of the Data Catalog where the functions to be retrieved are located. If none is provided, the AWS account ID is used by default.
+ `DatabaseName` – UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  The name of the catalog database where the functions are located. If none is provided, functions from all the databases across the catalog will be returned.
+ `Pattern` – *Required:* UTF-8 string, not less than 1 or more than 255 bytes long, matching the [Single-line string pattern](aws-glue-api-common.md#aws-glue-api-regex-oneLine).

  An optional function-name pattern string that filters the function definitions returned.
+ `NextToken` – UTF-8 string.

  A continuation token, if this is a continuation call.
+ `MaxResults` – Number (integer), not less than 1 or more than 100.

  The maximum number of functions to return in one response.

**Response**
+ `UserDefinedFunctions` – An array of [UserDefinedFunction](#aws-glue-api-catalog-functions-UserDefinedFunction) objects.

  A list of requested function definitions.
+ `NextToken` – UTF-8 string.

  A continuation token, if the list of functions returned does not include the last requested function.

**Errors**
+ `EntityNotFoundException`
+ `InvalidInputException`
+ `OperationTimeoutException`
+ `InternalServiceException`
+ `GlueEncryptionException`