The System ID that is assigned automatically by the Raiser's Edge System when a record is saved in Raiser's Edge Database. 

The Raiser's Edge, The Financial Edge, The Education Edge, and Blackbaud Student Information System are all relational databases. They are comprised of multiple tables linked on the back-end with the use of pointers. The pointers are called primary and foreign keys. Each table must have a primary key. This is a field that uniquely identifies each row in the table. The primary key links to a field in another table. This is called a foreign key. The System Record ID is the primary key for the Records Table. The Records Table is the table that stores biographical information.

In a Constituent Export, output Constituent information, System Record ID.

The System ID is assigned automatically by the system when a record is saved.

Note: To know how to get this ID for profiles individually refer to point 4.

Need not be. 

Users may notice that the System Record ID is different from the Constituent ID on constituent records. The System Record ID is automatically generated by the program when a record is added to the database and cannot be edited by the user.

The System Record ID does not have to match the Constituent ID (although a user can specify the System Record ID when importing a new record or by change the Constituent ID after the record has been saved to match the automatically generated System Record ID).  Each record must have a unique value in the database.  The Constituent ID can be reused after a constituent is deleted from the database but the System Record ID can never be reused.

References: 

Write to us at help@almabase.com in case of any queries.