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…]) syntax <!-- COPILOT_AI_GENERATED_START --> # Fix invalid OVER clause parsing - reject OVER([col]) syntax ## Summary Fixed a parser bug where invalid OVER clause syntax like `COUNT(*) OVER([col])` was incorrectly accepted. The parser now properly rejects OVER clauses that contain only an identifier in parentheses without PARTITION BY or ORDER BY clauses. ## Problem The parser was accepting invalid syntax such as: ```sql SELECT COUNT(*) OVER([col]) FROM t1 SELECT SUM(Amount) OVER(MyColumn) FROM t1 ``` This is invalid because an OVER clause with parentheses must contain one of: - `PARTITION BY` clause - `ORDER BY` clause - Window frame clause - Or be empty: `OVER()` Valid window name references (introduced in SQL Server 2022) must be written WITHOUT parentheses: ```sql SELECT SUM(c1) OVER Win1 FROM t1 WINDOW Win1 AS (PARTITION BY c1) ``` Additionally, partial window specifications CAN include a window name inside parentheses, but ONLY when combined with other clauses: ```sql SELECT SUM(c1) OVER (Win1 ORDER BY c2) FROM t1 WINDOW Win1 AS (PARTITION BY c1) ``` ## Root Cause In SQL Server 2022 (TSql160), support was added for the WINDOW clause feature, which allows referencing named windows. The grammar rule `overClauseBeginning` was modified to accept an optional identifier inside parentheses to support partial window specifications like `OVER (Win1 PARTITION BY ...)`. However, the rule `overClauseNoOrderBy` (used by aggregate functions like COUNT, SUM, AVG) was still using `overClauseBeginning`, which meant it would accept `OVER(identifier)` and interpret the identifier as a window name, even though no other clauses were present. This resulted in invalid syntax being accepted. ## Solution Created a new grammar rule `overClauseBeginningNoWindowName` that does not allow window name identifiers inside parentheses. Modified `overClauseNoOrderBy` to use this new rule instead of `overClauseBeginning`. The new rule uses explicit alternatives instead of an optional clause to ensure ANTLR properly rejects identifiers that aren't followed by the `BY` keyword: ```antlr overClauseBeginningNoWindowName: OVER LeftParenthesis ( Identifier { Match("PARTITION") } BY expressionList | /* empty - allow OVER() with no PARTITION BY */ ) ``` This ensures that when parsing `OVER([col])`, the parser will: 1. Try to match the PARTITION BY alternative 2. See the identifier but realize it's not followed by BY 3. Try the empty alternative 4. Fail because `[col]` is present when nothing was expected 5. Generate an error ## Files Modified - `SqlScriptDom/Parser/TSql/TSql160.g` - Added `overClauseBeginningNoWindowName` rule and updated `overClauseNoOrderBy` - `SqlScriptDom/Parser/TSql/TSql170.g` - Same changes as TSql160.g - `SqlScriptDom/Parser/TSql/TSql180.g` - Same changes as TSql180.g - `Test/SqlDom/ParserErrorsTests.cs` - Added `InvalidOverClauseNegative...
Adding release notes for 180.18.1 ---- #### AI description (iteration 1) #### PR Classification Documentation update adding release notes for version 180.18.1 of Microsoft.SqlServer.TransactSql.ScriptDom. #### PR Summary This pull request adds comprehensive release notes for version 180.18.1, documenting bug fixes, dependency updates, and changes to the SQL script generator. - `/release-notes/180/180.18.1.md`: Documents platform support for .NET Framework 4.7.2, .NET 8, and .NET Standard 2.0+ - `/release-notes/180/180.18.1.md`: Lists five parser bug fixes including TRIM clause parsing, DATEADD/DATEDIFF/DATEPART function argument handling, and OVER clause validation - `/release-notes/180/180.18.1.md`: Notes .NET SDK update to version 8.0.420 and script generator improvement for semicolon placement before trailing comments <!-- GitOpsUserAgent=GitOps.Apps.Server.pullrequestcopilot -->
llali
requested review from
chlafreniere,
dzsquared,
kburtram and
ssreerama
as code owners
dzsquared
approved these changes
May 1, 2026
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Sync repos: Release 180.18.1