The how-to topic listed above demonstrates how to run validation and view the results.To handle validation failures, consider the following: SQL Server validates data by calculating a row count or a checksum at the Publisher and then comparing those values to the row count or checksum calculated at the Subscriber.Here is an article showing how to check the md5sum of a file using Windows.This guide mentions that many other distributions now also use a GPG key to validate their files.When binary checksums are used, 32-bit redundancy check (CRC) occurs on a column-by-column basis rather than a CRC on the physical row on the data page.
These messages can be viewed in SQL Server Management Studio, Replication Monitor, and replication system tables.One value is calculated for the entire publication table and one value is calculated for the entire subscription table, but data in text, ntext, or image columns is not included in the calculations.While the calculations are performed, shared locks are placed temporarily on tables for which row counts or checksums are being run, but the calculations are completed quickly and the shared locks removed, usually in a matter of seconds.Keep in mind, though, that passing these tests is no guarantee that a card isn't stolen or canceled or that it belongs to a different person. The first determines card type, and the second determines whether the card checksum is correct.If the card passes both tests, the return value is the card type as a string. The first stage is where the big trick comes in, where we determine the card type and confirm the prefix in one quick step. For example, all Visas start with 4 and have 13 or 16 digits, all Master Cards start with 51 through 55 and have 16 digits, and all American Express cards start with 34 or 37 and have 15 digits.