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pgdeadbolt

change-column-type

Change column types with expand and contract.

Severity: error · Lock: ACCESS EXCLUSIVE

Most type changes rewrite the table and rebuild its indexes under ACCESS EXCLUSIVE. A few are metadata-only, such as varchar to text or making a varchar longer; if yours is one of them, ignore the finding.

Instead of

Section titled “Instead of”
ALTER TABLE events ALTER COLUMN id TYPE bigint;

Do

Section titled “Do”
ALTER TABLE events ADD COLUMN id_new bigint;
-- Write to both columns from the app, backfill old rows in batches,
-- switch reads to id_new, then drop id in a later deploy.

To skip this rule for one statement, put -- pgdeadbolt-ignore change-column-type on the line above it.