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Power Automate Add Field To ContentType (reference Microsoft)

Note the following restrictions on adding a field (column) to a content type using the REST service:

• Site Columns cannot be added to a content type using the REST service.
• You can add a field to a site content type only if the field already exists on the parent content type.
• You can add a field to a content type associated with a list only if the field already exists on the list. To add a completely new field to a list content type, you have to first add it to the list and then add it to the content type in a separate call to the REST service.

Invalid - Must not be used. The value = 0.

Integer - Specifies that the field contains an integer value. The value = 1.

Text - Specifies that the field contains a single line of text. The value = 2.

Note - Specifies that the field contains multiple lines of text. The value = 3.

DateTime - Specifies that the field contains a date and time value or a date-only value. The value = 4.

Counter - Specifies that the field contains a monotonically increasing integer. The value = 5.

Choice - Specifies that the field contains a single value from a set of specified values. The value = 6.

Lookup - Specifies that the field is a lookup field. The value = 7.

Boolean - Specifies that the field contains a Boolean value. The value = 8.

Number - Specifies that the field contains a floating-point number value. The value = 9.

Currency - Specifies that the field contains a currency value. The value = 10.

URL - Specifies that the field contains a URI and an optional description of the URI. The value = 11.

Computed - Specifies that the field is a computed field. The value = 12.

Threading - Specifies that the field indicates the thread for a discussion item in a threaded view of a discussion board. The value = 13.

Guid - Specifies that the field contains a GUID value. The value = 14.

MultiChoice - Specifies that the field contains one or more values from a set of specified values. The value = 15.

GridChoice - Specifies that the field contains rating scale values for a survey list. The value = 16.

Calculated - Specifies that the field is a calculated field. The value = 17.

File - Specifies that the field contains the leaf name of a document as a value. The value = 18.

Attachments - Specifies that the field indicates whether the list item has attachments. The value = 19.

User - Specifies that the field contains one or more users and groups as values. The value = 20.

Recurrence - Specifies that the field indicates whether a meeting in a calendar list recurs. The value = 21.

CrossProjectLink - Specifies that the field contains a link between projects in a Meeting Workspace site. The value = 22.

ModStat - Specifies that the field indicates moderation status. The value = 23.

Error - Specifies that the type of the field was set to an invalid value. The value = 24.

ContentTypeId - Specifies that the field contains a content type identifier as a value. The value = 25.

PageSeparator - Specifies that the field separates questions in a survey list onto multiple pages. The value = 26.

ThreadIndex - Specifies that the field indicates the position of a discussion item in a threaded view of a discussion board. The value = 27.

WorkflowStatus - Specifies that the field indicates the status of a workflow instance on a list item. The value = 28.

AllDayEvent - Specifies that the field indicates whether a meeting in a calendar list is an all-day event. The value = 29.

WorkflowEventType - Specifies that the field contains the most recent event in a workflow instance. The value = 30.

MaxItems - Must not be used. The value = 31.