Fix INSERT parser failing on double-parenthesized compound SELECT#98247
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alexey-milovidov merged 1 commit intomasterfrom Feb 27, 2026
Merged
Fix INSERT parser failing on double-parenthesized compound SELECT#98247alexey-milovidov merged 1 commit intomasterfrom
alexey-milovidov merged 1 commit intomasterfrom
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When `ASTSelectWithUnionQuery::formatQueryImpl` formats a compound SELECT (e.g., with `INTERSECT`/`EXCEPT`) that is a child of INSERT, it wraps nested unions in parentheses for correctness. This can produce queries like `INSERT INTO t1 ((SELECT 1) EXCEPT ALL (SELECT 2)) INTERSECT (SELECT 3)`. The INSERT parser failed to re-parse such queries because when it encountered `((SELECT ...`, it consumed the first `(` for the column list check, then failed to parse `(` as a column name and returned false immediately, instead of rewinding and letting the `(` be parsed as part of a SELECT query. The fix rewinds `pos` to before the `(` when column list parsing fails entirely, matching the existing behavior when column parsing succeeds but no closing `)` is found. Closes #90925 https://s3.amazonaws.com/clickhouse-test-reports/json.html?REF=master&sha=bfd26cd518682a2051429b51714e9c8c62806f45&name_0=MasterCI&name_1=BuzzHouse%20%28amd_debug%29&name_1=BuzzHouse%20%28amd_debug%29 Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
INTERSECT/EXCEPToperatorsINSERT INTO t1 ((SELECT 1) EXCEPT ALL (SELECT 2))), the parser now correctly handles the double parenthesesThe root cause: the INSERT parser consumed the first
(for column list parsing, but when the second(couldn't be parsed as a column name, it returnedfalseinstead of rewindingposto try parsing((SELECT ...)as a compound SELECT query.Closes #90925
CI report: https://s3.amazonaws.com/clickhouse-test-reports/json.html?REF=master&sha=bfd26cd518682a2051429b51714e9c8c62806f45&name_0=MasterCI&name_1=BuzzHouse%20%28amd_debug%29&name_1=BuzzHouse%20%28amd_debug%29
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