fix(restore): eliminate O(N^2) linear scan in getTableListByPatternLocal#1430
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fix(restore): eliminate O(N^2) linear scan in getTableListByPatternLocal#1430ruslanen wants to merge 1 commit into
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addTableToListIfNotExistsOrEnrichQueryAndParts iterated the full result slice for every file processed during filepath.Walk. With 550K tables this produced N*(N-1)/2 ~ 151 billion string comparisons (~2 hours). Fix: maintain a tableIndex map[TableTitle]int alongside the result slice. Lookup and enrich are now O(1); total restore init phase drops from O(N^2) to O(N). The inline addToResult closure replaces the two local call sites; the original function is kept for the remote-restore path which operates on far fewer tables in practice.
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addTableToListIfNotExistsOrEnrichQueryAndParts iterated the full result slice for every file processed during filepath.Walk. With 550K tables this produced N*(N-1)/2 ~ 151 billion string comparisons (~2 hours).
Fix: maintain a tableIndex map[TableTitle]int alongside the result slice. Lookup and enrich are now O(1); total restore init phase drops from O(N^2) to O(N). The inline addToResult closure replaces the two local call sites; the original function is kept for the remote-restore path which operates on far fewer tables in practice.