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How not to change PostgreSQL column type
Deep dive into SQL & PostgreSQL to build reliable, rock-solid solutions with tips and tricks that keep business online. Data is everything. Explore, learn and innnovate to get them where you need faster and more efficiently.
Generating a large volume of changes (and therefore WAL files) can leave the less performant (or infrequent) replication systems behind for a considerable amount of time. The problem is, therefore (and I will repeat myself), the scale of the amount of data being modified, overall congestion of the system, I/O capacity, and the target table's importance in the application design. While changing the column type in PostgreSQL can be as simple as issuing an ALTER TABLE command, it is important for everyone involved to understand the complexities attached to it.
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