sqlstore: replace LIKE queries with range queries for index-friendly#1091
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tovmeod wants to merge 1 commit intotulir:mainfrom
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sqlstore: replace LIKE queries with range queries for index-friendly#1091tovmeod wants to merge 1 commit intotulir:mainfrom
tovmeod wants to merge 1 commit intotulir:mainfrom
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…PN-to-LID migration
The MigratePNToLID and deleteAll* functions used LIKE patterns (e.g.
`their_id LIKE $2 || ':%'`) which PostgreSQL cannot optimize with btree
indexes when the pattern is parameterized. This caused sequential scans
on large tables (sender_keys 1.7M rows/2GB, sessions 248K rows/2.4GB)
on every new sender during message decryption.
Replace LIKE with equivalent range queries using ASCII ordering:
`their_id >= $2 || ':' AND their_id < $2 || ';'`
(':' is ASCII 58, ';' is ASCII 59, so this matches exactly the same
rows as LIKE 'phone:%')
This allows PostgreSQL to use the existing btree primary key indexes
for efficient range scans instead of sequential table scans.
Also fix DeleteIdentity to use deleteIdentityQuery (exact match)
instead of deleteAllIdentitiesQuery (was doing a LIKE match on a
single address, which happened to work but was semantically wrong).
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sqlstore: replace LIKE queries with range queries for index-friendly PN-to-LID migration
The MigratePNToLID and deleteAll* functions used LIKE patterns (e.g.
their_id LIKE $2 || ':%') which PostgreSQL cannot optimize with btree indexes when the pattern is parameterized. This caused sequential scans on large tables (sender_keys 1.7M rows/2GB, sessions 248K rows/2.4GB) on every new sender during message decryption.Replace LIKE with equivalent range queries using ASCII ordering:
their_id >= $2 || ':' AND their_id < $2 || ';'(':' is ASCII 58, ';' is ASCII 59, so this matches exactly the same rows as LIKE 'phone:%')
This allows PostgreSQL to use the existing btree primary key indexes for efficient range scans instead of sequential table scans.
Also fix DeleteIdentity to use deleteIdentityQuery (exact match) instead of deleteAllIdentitiesQuery (was doing a LIKE match on a single address, which happened to work but was semantically wrong).