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Yes, MSSQL does support transactional DDL, via locking rather than versioning. Not sure how PostresSQL implements it. Anyone? Row versioning would be more concu

Yes, MSSQL does support transactional DDL, via locking rather than versioning. Not sure how PostresSQL implements it. Anyone? Row versioning would be more concurrency-friendly, and arguably more "right". I'd be interested if anyone took advantage of versioned transactional DDL to persist arbitrary data structures on the fly.

mmt 16y ago
Postgres does it with versioning, as that's how everything is stored on disk. As I've seen DDL outside of a transaction take much longer than inside one, it may use locking there.