Following my last posts on Change Data Capture and Change Tracking, here is another tip regarding tracking changes: table and colum checksums.

The concept is: each time a column value changes, the checksum also changes. You can use this simple method to see if a table has changed very easily, however, beware, different column values may generate the same checksum. Here's the SQL:

-- table checksum
SELECT CHECKSUM_AGG(BINARY_CHECKSUM(*)) FROM TableName

-- column checksum
SELECT CHECKSUM_AGG(BINARY_CHECKSUM(ColumnName)) FROM TableName

-- integer column checksum
SELECT CHECKSUM_AGG(IntegerColumnName) FROM TableName

Here are the reference links on the CHECKSUM, CHECKSUM_AGG and BINARY_CHECKSUM functions:

• CHECKSUM
• CHECKSUM_AGG
• BINARY_CHECKSUM