How to delete large number of rows without affecting Informatica replication?

Question

I'm not exactly sure if it will cause an issue or not. But in our environment whenever selecting from large tables we need to include WITH(nolock) otherwise we get deadlocks between select statements and Informatica real time replication trying to populate those tables. Currently we are looking to use SQL jobs to purge old records from tables. Most tables will have less than 1000 rows deleted once a week. During initial purge process there will be several tables that will have millions of records deleted.

Not sure if it would be better to pause real time replication for duration of the purge or just to try to resolve conflicts once those arise.

I don't have a good way to test this in Dev environment because don't have same volume of people hitting server with request, real time updates and everything else that makes up normal load in production. In production this will be running once a week during slow hours that should minimize total load but still don't want to crash Informatica every time this is running.

Note: this question is NOT about how to write delete statements in SQL or breaking delete in small chunks but rather how to avoid conflicts with real time replication with Informatica product.

Database - SQL Server 2012
Replication - Informatica 9.0.1

Answer 1

How about escalating the lock for the time of purging? If you initially lock all pages needed (or set a table-level lock), perform the purge and then release the lock, no deadlocks shouls occure. And this will not require any updates for replication process.