Question

When using the SOAP API to work with salesforce.com (SFDC) it seems that the primary key in the underlying database is Id. Well there seems to be two representations of this value as either a 15 character version or an 18 character version.

I have been using the 18 since it is clearly more specific, but what is contained in the last three digits, that they can be dropped, seemingly?

Anyone understand what this is all about?

Answer 1

From the Web Services API Developer’s Guide:

ID fields in the Salesforce.com user
interface contain 15-character,
base-62, case-sensitive strings. Each
of the 15 characters can be a numeric
digit (0-9), a lowercase letter (a-z),
or an uppercase letter (A-Z). Two
unique IDs may only be different by a
change in case.

Because there are applications like
Access which do not recognize that
50130000000014c is a different ID from
50130000000014C, an 18-digit,
case-safe version of the ID is
returned by all API calls. The 18
character IDs have been formed by
adding a suffix to each ID in the
Force.com API. 18-character IDs can be
safely compared for uniqueness by
case-insensitive applications, and can
be used in all API calls when
creating, editing, or deleting data.

If you need to convert the
18-character ID to a 15-character
version, truncate the last three
characters. Salesforce.com recommends
that you use the 18-character ID.