I once wrote about this problem, but given that we now have DO blocks and procedures I can make nicer, easy to use example.
Continue reading How to ALTER tables without breaking application?
Tag: loop
How to run short ALTER TABLE without long locking concurrent queries
Recently I've seen case like:
- application had to add column to table.
- application ran ALTER TABLE ADD COLUMN (without default!)
- everything stopped for many MINUTES
Why? How to avoid the problem?
Continue reading How to run short ALTER TABLE without long locking concurrent queries
Explaining the unexplainable – part 3
In previous post in the series I wrote about how to interpret single line in explain analyze output, it's structure, and later on described all basic data-getting operations (nodes in explain tree).
Today, we'll move towards more complicated operations.