Re: confusion between max_standby_archive_delay, max_standby_archive_delay and max_standby_archive_delay

On 3/11/23 14:23, Atul Kumar wrote:

Hi,

Could someone help me in telling the difference between these three parameters 

1. max_standby_archive_delay

2. max_standby_streaming_delay

3. recovery_min_apply_delay

My basic motive is to make the standby database server to be delayed to apply the changes on itself,  if any data has been accidentally deleted/updated/ truncated from the primary server.

What you're looking for is that WAL files be "aggregated and optimized" by removing statements which don't have any impact on the final state of instance.

That's great for restoring instances with update-heavy databases, and can only implemented by backup/restore software, or roll-your-own log shipping.  Just as importantly, that aggregation-optimization software has it's own costs (time and disk space), since it takes time to scan through all the recovery logs, keeping track of what must stay, what can be tossed, and the final state.