# Create a Data Extension Use a data extension to store information about your subscribers. ## Data Extension Considerations Keep these considerations in mind when you use SOAP API to create data extensions: - Limit data extension external keys to 36 characters. You can specify an external key that exceeds this limit, but doing so can negatively impact other processes. - Don't use `Date` values as primary keys. When you retrieve a column that contains the `Date` data type, SOAP API returns a value that’s rounded to the nearest second, followed by AM or PM. This behavior occurs even when the source timestamp contains millisecond data. As a result, if you use a `Date` column as a primary key, it can prevent you from retrieving unique rows. ## Sample SOAP Create Request This sample SOAP envelope represents a request to create a data extension called DataExtensionFromAPI. The data extension contains 4 fields: EmailAddress, ChannelUser, ChannelUser_EmailAddress, and Demographic_Address. ```xml DataExtensionFromAPI DataExtensionFromAPI true EmailAddress_Key EmailAddress EmailAddress Email Address EmailAddress_Key EmailAddress EmailAddress ChannelUser_Key ChannelUser Text ChannelUser_EmailAddress_Key ChannelUser_EmailAddress EmailAddress Demographic_Address_Key Demographic_Address Text ``` ## Sample SOAP Create Response If the API accepts the request to create a data extension, the response includes the external key, name, and fields for the data extension. ```xml OK Data Extension created. 0 0 1a3e2c14-580e-de11-b30f-001cc494ae9e 1a3e2c14-580e-de11-b30f-001cc494ae9e DataExtensionFromAPI DataExtensionFromAPI true EmailAddress_Key EmailAddress EmailAddress Email Address EmailAddress_Key EmailAddress EmailAddress ChannelUser_Key ChannelUser Text ChannelUser_EmailAddress_Key ChannelUser_EmailAddress EmailAddress Demographic_Address_Key Demographic_Address Text 27a2d45f-0eef-4118-b4de-fde288b09657 OK ``` ## Create a Data Extension with Non-Nullable Fields This sample SOAP envelope creates a data extension with a non-nullable field by including `IsPrimaryKey` and `IsRequired` values. ```xml yoni_test_10 yoni_test_1 Created from API on 2024-02-08 true true userid EmailAddress Subscriber Key userid userid true true EmailAddress geoid geoid Number Number order order Number Number url url Text 1000 true false Text time time Date true false Date ``` ## Create a Data Extension that uses Different Field Types This sample SOAP envelope includes an example of data extension field types. ```xml FieldTypeTest false EmailAddress_type EmailAddress true true Text_type Text false Date_type Date getdate() true Decimal_type Decimal true 10 2 Boolean_type Boolean true true Number_type Number false Phone_type Phone false Locale_type Locale false FieldTypeTest ``` ## Create a Data Extension with Row-Based Data Retention This example shows how to create a data extension that uses row-based data retention. In a data extension that uses row-based retention, individual rows are deleted when their ages exceed the specified period. ```xml Create https://YOUR_SUBDOMAIN.soap.marketingcloudapis.com/Service.asmx YOUR_ACCESS_TOKEN 987654 c7b0df2e-e34a-11ef-a842-325096b39f69 DE with Row-Based Retention true SubscriberKey SubscriberKey Text Subscriber Key 48 Days true SubscriberKey SubscriberKey Text 50 true true First_Name First_Name Text 50 false false Last_Name Last_Name Text 50 false false Email Email EmailAddress false false Rewards_Points Rewards_Points Number false false ``` ## Create a Data Extension with Object-Based Data Retention This example shows how to create a data extension that uses object-based data retention. In a data extension that uses object-based retention, all of the content in the data extension is deleted after the specified period. Optionally, you can delete the data extension itself (rather than just the data within it) at the end of the retention period by setting `DeleteAtEndOfRetentionPeriod` to `false`. If you set this to `true`, only the content is deleted after the specified period, but the data extension persists. Compared to the row-based retention code example, this example omits the `RowBasedRetention` property and adds the `ResetRetentionPeriodOnImport` and `DeleteAtEndOfRetentionPeriod` properties. ```xml Create https://YOUR_SUBDOMAIN.soap.marketingcloudapis.com/Service.asmx YOUR_ACCESS_TOKEN 987654 c7b0df2e-e34a-11ef-a842-325096b39f69 DE with Object-Based Retention true SubscriberKey SubscriberKey Text Subscriber Key 48 Days true false SubscriberKey SubscriberKey Text 50 true true First_Name First_Name Text 50 false false Last_Name Last_Name Text 50 false false Email Email EmailAddress false false Rewards_Points Rewards_Points Number false false ``` ## Create a Data Extension that Includes a Date Value in a Date-type Field When you create a data extension field that contains a date value, pass the time in 24-hour format. ``` DateFormatTest DateField ``` ## See Also - [Retrieve Data from a Data Extension](/docs/marketing/marketing-cloud/guide/retrieving_data_from_a_data_extension.md)