Fix SQL quoted qualified name matching

changelog.d/unreleased/2101.fixed.md

@@ -0,0 +1,18 @@
+---
+category: fixed
+issues:
+  - 2101
+affected:
+  - src/CodeIndex/Database/DbContext.cs
+  - src/CodeIndex/Database/DbSymbolReader.cs
+  - src/CodeIndex/Indexer/References/Support/SqlNameResolver.cs
+  - tests/CodeIndex.Tests/ReferenceExtractorTests.cs
+---
+
+## English
+
+- **SQL quoted qualified names now respect dialect matching rules (#2101)** — schema-qualified SQL references keep MySQL backtick and T-SQL bracket matching case-insensitive while preserving PostgreSQL double-quoted identifier case sensitivity.
+
+## 日本語
+
+- **SQL の引用付き qualified name が dialect ごとの照合規則を尊重するようになりました (#2101)** — schema 修飾された SQL 参照では MySQL のバッククォートと T-SQL のブラケットは大文字小文字を区別しない照合を維持しつつ、PostgreSQL の二重引用符付き識別子は大文字小文字を区別します。

src/CodeIndex/Database/DbContext.cs

@@ -647,6 +647,10 @@ internal static void RegisterConnectionFunctions(SqliteConnection connection)
                 && segmentCount > 0
                     ? segmentCount
                     : null));
+        connection.CreateFunction(
+            "sql_reference_matches_target_at",
+            (string? symbolName, string? context, string? containerName, long? columnNumber, string? targetName) =>
+                SqlNameResolver.ReferenceMatchesTargetAtColumn(symbolName, context, containerName, ToNullableInt(columnNumber), targetName) ? 1 : 0);
         connection.CreateFunction(
             "sql_allow_leaf_fallback_at",
             (string? symbolName, string? context, string? containerName, long? columnNumber) =>

src/CodeIndex/Database/DbSymbolReader.cs

@@ -2570,7 +2570,7 @@ FROM symbol_references sr
                       WHERE sr.symbol_name = s.name
                          OR (f.lang = 'sql' AND rf.lang = 'sql' AND (
                                 (sql_resolve_reference_segment_count_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number) = sql_segment_count(s.name)
-                                 AND sql_resolve_reference_name_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number) = sql_normalize_name(s.name) COLLATE NOCASE)
+                                 AND sql_reference_matches_target_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number, s.name) = 1)
                          OR (sql_segment_count(sr.symbol_name) = 1
                             AND sql_allow_leaf_fallback_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number) = 1
                             AND sr.symbol_name = sql_leaf_name(s.name) COLLATE NOCASE
@@ -2580,7 +2580,7 @@ FROM symbols s_exact
                                     JOIN files f_exact ON f_exact.id = s_exact.file_id
                                     WHERE f_exact.lang = 'sql'
                                       AND sql_segment_count(s_exact.name) = sql_resolve_reference_segment_count_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number)
-                                     AND sql_normalize_name(s_exact.name) = sql_resolve_reference_name_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number) COLLATE NOCASE
+                                     AND sql_reference_matches_target_at(sr.symbol_name, " + ReferenceContextSql("sr") + @", sr.container_name, sr.column_number, s_exact.name) = 1
                                 ))
                          ))
                   )";
@@ -2726,7 +2726,7 @@ FROM symbol_references sr
                   WHERE sr.symbol_name = s.name
                      OR (f.lang = 'sql' AND rf.lang = 'sql' AND (
                             (sql_resolve_reference_segment_count_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number) = sql_segment_count(s.name)
-                             AND sql_resolve_reference_name_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number) = sql_normalize_name(s.name) COLLATE NOCASE)
+                             AND sql_reference_matches_target_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number, s.name) = 1)
                          OR (sql_segment_count(sr.symbol_name) = 1
                             AND sql_allow_leaf_fallback_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number) = 1
                             AND sr.symbol_name = sql_leaf_name(s.name) COLLATE NOCASE
@@ -2736,7 +2736,7 @@ FROM symbols s_exact
                                     JOIN files f_exact ON f_exact.id = s_exact.file_id
                                     WHERE f_exact.lang = 'sql'
                                       AND sql_segment_count(s_exact.name) = sql_resolve_reference_segment_count_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number)
-                                      AND sql_normalize_name(s_exact.name) = sql_resolve_reference_name_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number) COLLATE NOCASE
+                                      AND sql_reference_matches_target_at(sr.symbol_name, " + contextSql + @", sr.container_name, sr.column_number, s_exact.name) = 1
                                 ))
                      ))
               )";