Line pointers across DELETE and VACUUM
VACUUM frees tuple space by moving line pointers 1 (normal) to 3 (dead) to 0 (unused).
task
Delete ids 1 to 50, VACUUM lab.t, then count line pointers per lp_flags, ordered by lp_flags.
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- [ ] is not distinct from reaches the index
- [ ] physical correlation
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- [ ] skip scan on a b tree
- [ ] walk the root page
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- [ ] boss one row about a table
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- [ ] pg stats knows the table oid
- [ ] statistics on a boolean function
- [ ] the index behind a primary key
- [ ] what pg class says about a table
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- [ ] a fresh file after repack
- [ ] a partitioned table needs an index name
- [ ] a read sets all visible without vacuum
- [ ] boss one vacuum cycle
- [ ] dead item memory in vacuum verbose
- [ ] line pointers across delete and vacuum
- [ ] relfrozenxid advances
- [ ] repack concurrently
- [ ] repack using index orders the heap
- [ ] the visibility map after vacuum
- [ ] vacuum full gives the space back
- [ ] which table would autovacuum pick
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- [ ] an impossible predicate
- [ ] coalesce stops at the first not null argument
- [ ] incremental sort under append
- [ ] is not distinct from reaches the index
- [ ] is null on any not null column of the inner side
- [ ] memoize under an anti join
- [ ] read stream counters in explain io
- [ ] read the memoize estimate
- [ ] turn eager aggregation off
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- [ ] aggregate support clause
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- [ ] check not enforced promote
- [ ] checkpoint options
- [ ] conflict select needs returning
- [ ] copy header n
- [ ] copy json header error
- [ ] copy multiline header out
- [ ] copy partitioned roundtrip
- [ ] copy set null
- [ ] distinct from null folding
- [ ] eager aggregate
- [ ] grant granted by
- [ ] group subquery expr
- [ ] group subquery grouping
- [ ] inet gist default
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- [ ] jit off
- [ ] json array empty
- [ ] jsonpath colors upper
- [ ] no crlf in names
- [ ] notin antijoin
- [ ] notin nullable
- [ ] oid8 validation
- [ ] psql display true
- [ ] psql search path prompt
- [ ] random dates
- [ ] regdatabase lookup
- [ ] repack concurrently
- [ ] repack index order
- [ ] repack partitioned needs index
- [ ] schema forward fk
- [ ] scs always on
- [ ] search path null
- [ ] skip scan
- [ ] stemmer dictionaries
- [ ] subscription server
- [ ] temporal oncall
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- [ ] uuid from md5
- [ ] uuid from sha256 error
- [ ] virtual default
- [ ] virtual set expression
- [ ] virtual set expression violation
- [ ] wait for lsn
- [ ] win ignore rank error
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