# Creating and populating a new ID mapping table
<a name="create-id-mapping-table"></a>

**Prerequisites**

Before creating an ID mapping table, ensure you have:
+ An associated ID namespace source and target
+ The ID namespaces configured for either rule-based ID mapping or provider services ID mapping

  

You can create two types of ID mapping tables:
+ Rule-based – Uses matching rules to translate first-party data
+ Provider services – Uses LiveRamp to translate RampIDs

After you create an ID mapping table, you can either populate it immediately by running an ID mapping workflow, or you can wait to populate the table later. 

After the ID mapping table is successfully populated, you can then run a multi-table join query on the ID mapping table to join the `sourceId` with the `targetId` and analyze the data.

**Topics**
+ [Create an ID mapping table (rule-based)](#create-id-mapping-table-rule-based)
+ [Create an ID mapping table (provider services)](#create-id-mapping-table-provider-services)

## Create an ID mapping table (rule-based)
<a name="create-id-mapping-table-rule-based"></a>

This topic describes the process of creating an ID mapping table that uses matching rules to translate first-party data from a source to a target. 

When you create a rule-based ID mapping table, you can choose to process only new, updated, or deleted records in the workflow by turning on incremental processing. 

**To create and populate a new ID mapping table using the rule-based method**

1. Sign in to the AWS Management Console and open the AWS Clean Rooms console at [https://console.aws.amazon.com/cleanrooms/](https://console.aws.amazon.com/cleanrooms/).

1. In the navigation pane, choose **Collaborations**.

1. Choose the collaboration, and then choose the **Entity resolution** tab.

1. Choose **Create ID mapping table**.

1. Under **ID mapping settings**, do one of the following:
   + To create a new workflow, keep **Create a new ID mapping workflow** selected.
   + To use an existing workflow, clear the checkbox and select a workflow from the dropdown list, then skip to step 9.

1. Under **Identity data**, view or configure the source and target.
   + For a single ID namespace pair: Review the pre-selected **Source** and **Target**. 
   + For multiple ID namespaces: Select the **Source** and **Target** from the dropdown lists. 

1. (Optional) Select **Turn on incremental processing** to process only new, updated, or deleted records in the workflow.

   AWS Entity Resolution processes only new, updated, or deleted records in either the Source or Target ID namespace, rather than recreating the entire ID mapping table. 

   If you leave this option unselected, AWS Entity Resolution runs the default batch processing ID mapping workflow on the ID mapping table. 

1. Under **Rule parameters**, configure the following:
   + **Rule controls** – Choose whether the **Target** or **Source** provides matching rules.

     You can view the rules by turning on **Show rules**.

     Rule controls must be compatible between the source and the target ID namespace to be used in an ID mapping workflow. For example, if a source ID namespace limits rules to the target but the target ID namespace limits rules to the source, this results in an error.
   + **Comparison type** is automatically set to **Multiple input fields.**

     This is because both participants had selected this option previously. 
   + **Record matching**
     + **One source to one target** – Stores one matching record per target 
     + **Many sources to one target** – Stores all matching records per target 
**Note**  
The limitations specified for the source and target ID namespaces must be compatible. 

1. For **ID mapping details**, configure the following: 

   1. Enter an **ID mapping table name** or keep the default name.

   1. (Optional) Enter a **Description** of the ID mapping table.

      The description helps with writing queries.

1. For **AWS Clean Rooms access**, choose one: 
   + **Allow AWS Clean Rooms to add and manage permission policy** – Creates a service role automatically.
   + **Add and manage permissions manually** – Either review and modify the resource policy or choose **Add policy statement**.
**Note**  
If you can’t modify the role policy, you receive an error message stating that AWS Clean Rooms couldn't find the policy for the service role.

1. For **AWS Entity Resolution access**, choose one:

   This section is only visible if you're creating a new ID mapping table.
   + **Create and use a new service role**
     + The default Service role name is `entityresolution-id-mapping-workflow-<timestamp>`
     + (Optional) For encrypted data, select **This data is encrypted by a KMS key** and enter the **AWS KMS key**.
   + **Use an existing service role**
     + Choose an **Existing service role name** from the dropdown list or enter a role ARN.

       The list of roles are displayed if you have permissions to list roles.

       View the service role by choosing the **View in IAM** external link.

       If there are no existing service roles, the option to **Use an existing service role** is unavailable.

       By default, AWS Clean Rooms doesn't attempt to update the existing role policy to add necessary permissions.
     + (Optional) Select **Add a pre-configured policy with necessary permissions to this role** to attach necessary permissions to the role. 

       You must have permissions to modify roles and create policies.

1. (Optional) Under **Additional settings**, configure: 

   1. **ID mapping table settings**
      + To enable custom encryption, choose **Customize encryption settings** and enter an AWS KMS key.
**Note**  
 This KMS key needs to grant the required permissions to use within AWS Entity Resolution to `cleanrooms.amazonaws.com` using a KMS key policy. For more details about the required permissions for working with encryptions with an ID mapping workflow, see [Create a workflow job role for AWS Entity Resolution](https://docs.aws.amazon.com/entityresolution/latest/userguide/create-workflow-job-role.html) in the *AWS Entity Resolution User Guide*.
      + To add tags, choose **Add new tag** and enter key-value pairs 

   1. **ID mapping workflow settings** (new workflows only):
      + To use different names, clear **Keep the same ID mapping table name and description ** and enter new values.
      + To add tags, choose **Add new tag** and enter key-value pairs 

1. Choose one of the following:
   + **Create ID mapping table** – Creates an empty table you can populate later ([Populating an existing ID mapping table](populate-id-mapping-table.md))
   + **Create and populate ID mapping table** – Creates and immediately populates the table (may take several hours)

   The ID mapping workflow process begins. During this process, the ID mapping table is populated with translated IDs. The ID mapping workflow might take a few hours to process. 

   After the ID mapping table is successfully populated, you can [query the ID mapping table](query-id-mapping-tables.md) to join the `sourceId` with the `targetId` and analyze the data. 

## Create an ID mapping table (provider services)
<a name="create-id-mapping-table-provider-services"></a>

This topic describes the process of creating an ID mapping table that uses a provider service (LiveRamp). The LiveRamp provider services translates a set of source RampIDs to another using either maintained or derived RampIDs. 

**To create a new ID mapping table using the provider services method**

1. Sign in to the AWS Management Console and open the AWS Clean Rooms console at [https://console.aws.amazon.com/cleanrooms/](https://console.aws.amazon.com/cleanrooms/).

1. In the navigation pane, choose **Collaborations**.

1. Choose the collaboration, and then choose the **Entity resolution** tab.

1. Choose **Create ID mapping table**.

1. Under **ID mapping settings**, do one of the following:
   + To create a new workflow, keep **Create a new ID mapping workflow** selected.
   + To use an existing workflow, clear the checkbox and select a workflow from the dropdown list, then skip to step 9.

1. Under **Identity data**, view or configure the source and target.
   + For a single ID namespace pair: Review the pre-selected **Source** and **Target**.
   + For multiple ID namespaces: Select the **Source** and **Target** from the dropdown lists.

1. Under **Method**, verify that the selected ID mapping workflow method is **LiveRamp transcoding**.

1. For **LiveRamp configurations**, do one of the following:
   + Enter the **LiveRamp ID manager ARN** and **LiveRamp secret manager ARN**.
   + Choose **Import from existing workflow**.

1. For **ID mapping details**, configure the following: 

   1. Enter an **ID mapping table name** or keep the default name.

   1. (Optional) Enter a **Description** of the ID mapping table.

      The description helps with writing queries.

1. For **AWS Clean Rooms access**, choose one: 
   + **Allow AWS Clean Rooms to add and manage permission policy** – Creates a service role automatically.
   + **Add and manage permissions manually** – Either review and modify the resource policy or choose **Add policy statement**.
**Note**  
If you can’t modify the role policy, you receive an error message stating that AWS Clean Rooms couldn't find the policy for the service role.

1. For **AWS Entity Resolution access ** choose one:

   This section is only visible if you're creating a new ID mapping table.
   + **Create and use a new service role**
     + The default Service role name is `entityresolution-id-mapping-workflow-<timestamp>`
     + (Optional) For encrypted data, select **This data is encrypted by a KMS key** and enter the **AWS KMS key**.
   + **Use an existing service role**
     + Choose an **Existing service role name** from the dropdown list or enter a role ARN.

       The list of roles are displayed if you have permissions to list roles.

       View the service role by choosing the **View in IAM** external link.

       If there are no existing service roles, the option to **Use an existing service role** is unavailable.

       By default, AWS Clean Rooms doesn't attempt to update the existing role policy to add necessary permissions.
     + (Optional) Select **Add a pre-configured policy with necessary permissions to this role** to attach necessary permissions to the role. 

       You must have permissions to modify roles and create policies.

1. (Optional) Under **Additional settings** configure: 

   1. **ID mapping table settings**
      + To enable custom encryption, choose **Customize encryption settings** and enter an AWS KMS key.
**Note**  
 This KMS key needs to grant the required permissions to use within AWS Entity Resolution to `cleanrooms.amazonaws.com` using a KMS key policy. For more details about the required permissions for working with encryptions with an ID mapping workflow, see [Create a workflow job role for AWS Entity Resolution](https://docs.aws.amazon.com/entityresolution/latest/userguide/create-workflow-job-role.html) in the *AWS Entity Resolution User Guide*.
      + To add tags, choose **Add new tag** and enter key-value pairs.

   1. **ID mapping workflow settings** (new workflows only):
      + To use different names, clear **Keep the same ID mapping table name and description ** and enter new values.
      + To add tags, choose **Add new tag** and enter key-value pairs.

1. Choose one of the following:
   + **Create ID mapping table** – Creates an empty table you can populate later ([Populating an existing ID mapping table](populate-id-mapping-table.md))
   + **Create and populate ID mapping table** – Creates and immediately populates the table (may take several hours)

   The ID mapping workflow process begins. During this process, the ID mapping table is populated with translated IDs. The ID mapping workflow might take a few hours to process. 

   After the ID mapping table is successfully populated, you can [query the ID mapping table](query-id-mapping-tables.md) to join the `sourceId` with the `targetId` and analyze the data.