Use an email address to retrieve a member ID

The best way to check for the existence of a single member by email address is to use the following request:

API request format

GET /membervalues?membervariablename=email&membervariablevalue={email address}&fields=memberid&sort=effectivedate:d&limit=1

If	Then
A member ever used this email address	One item is returned.
No member has ever had this email address	Then an empty collection is returned.

Note: The resource /membervalues should be used rather than /membervalues/asof/{datetime}, because the email address for a member can change over time. Using /membervalues/asof/{datetime} would miss cases where the email address in the request is not the latest.

For more information, see /membervalues.

Content control

The following parameters are not required, but reduce the amount of information returned:

Parameter	Description
fields=memberid	Reduces the number of properties returned to the bare minimum.
sort=effectivedate:d&limit=1	Sorts items by effective date in descending order and reduces the number of items returned to 1 (where there could be more than one if the email address had been set multiple times).

• Request current information about members
  You can request current information for one or more members at a time by sending the following request.
• Get an incremental stream of changes to Member Values
  Monitor any incremental changes to Member Values in your community.
• POST a Member Variable
  You can create several Member Variables with different types of properties in a single request.
• Assign a collection of Member Values
  Before assigning a collection of Member Values, check to see if a member exists to:
• Create a member and assign values
  A member is created when a POST request including memberEmail is sent to /membervalues, as long as that email has never been assigned to a member.
• Create a new member with detail
  There is no direct members resource that can be called to create a member. Instead, a member is created when a POST request including memberEmail is sent to /membervalues, as long as that email has never been assigned to a member.
• Create a new member without detail
  You can create a new member without providing detailed information about them, such as their date of birth or annual income.
• Check current Member Values before reassigning
  Most functionality within the platform relies on the latest Member Values. Since Member Values are a time-series, it is possible to POST the same information for a given member (e.g. City=Vancouver) many times without noticeable functional implications. Doing so will simply record that City=Vancouver was known to be true at these several points in time.
• Add or remove a Member Variable from the profile
  Use the profileVariable category to control whether a specific Member Variable will appear in the UI for the purposes of targeting members, exporting data, and reporting.