# Update Mainframe Dataset metadata by ID

Endpoint: PUT /mainframe-dataset-metadata/{mainframeDatasetMetadataId}
Version: 5.1.42
Security: api_key

## Path parameters:

  - `mainframeDatasetMetadataId` (integer, required)
    The ID of the Mainframe Dataset metadata to update

## Request fields (application/json):

  - `fileName` (string, required)
    The name of the Mainframe Dataset metadata. This name must match the name of a file in the ruleset it is created on. This name must be unique for the given ruleset; in other words, the same file cannot be added to a ruleset more than once.
    Example: "file.dat"

  - `rulesetId` (integer, required)
    The ID of the ruleset to create the Mainframe Dataset metadata on.
    Example: 1

  - `mainframeDatasetFormatId` (integer)
    The ID of the Mainframe Dataset format corresponding to this Mainframe Dataset metadata. It is used to determine the fields for this file. This field is required.
    Example: 2

  - `recordFormat` (string)
    The record format type for the mainframe data set. Note that this enum corresponds to the Variable Length checkbox in the UI.
    Enum: "FIXED_BLOCKED", "VARIABLE_BLOCKED"

  - `nameIsRegularExpression` (boolean)
    Whether or not this file name represents a regular expression.

## Response 200 fields (application/json):

  - `mainframeDatasetMetadataId` (integer)
    The ID of the Mainframe Dataset metadata. This field is set by the Masking Engine.

  - `fileName` (string, required)
    The name of the Mainframe Dataset metadata. This name must match the name of a file in the ruleset it is created on. This name must be unique for the given ruleset; in other words, the same file cannot be added to a ruleset more than once.
    Example: "file.dat"

  - `rulesetId` (integer, required)
    The ID of the ruleset to create the Mainframe Dataset metadata on.
    Example: 1

  - `mainframeDatasetFormatId` (integer)
    The ID of the Mainframe Dataset format corresponding to this Mainframe Dataset metadata. It is used to determine the fields for this file. This field is required.
    Example: 2

  - `recordFormat` (string)
    The record format type for the mainframe data set. Note that this enum corresponds to the Variable Length checkbox in the UI.
    Enum: "FIXED_BLOCKED", "VARIABLE_BLOCKED"

  - `nameIsRegularExpression` (boolean)
    Whether or not this file name represents a regular expression.


## Response 400 fields

## Response 404 fields