diff --git a/apps/desktop/src/components/editor/QueryEditor.vue b/apps/desktop/src/components/editor/QueryEditor.vue
index a99d96154f..b25390b0f4 100644
--- a/apps/desktop/src/components/editor/QueryEditor.vue
+++ b/apps/desktop/src/components/editor/QueryEditor.vue
@@ -133,6 +133,7 @@ import { normalizeShortcutSettings, shortcutToCodeMirrorKey } from "@/lib/editor
 import { trimmedSelectionLayer } from "@/lib/editor/codemirrorTrimmedSelectionLayer";
 import { currentStatementFrameLayer } from "@/lib/editor/codemirrorCurrentStatementFrameLayer";
 import { selectionMatchOccurrences } from "@/lib/editor/codemirrorSelectionMatches";
+import { createSqlAliasHighlights } from "@/lib/editor/codemirrorSqlAliasHighlights";
 import { createInsertValueHintsExtension, requestInsertValueHintsRefresh, supportsInsertValueHints } from "@/lib/editor/codemirrorInsertValueHints";
 import { sqlBlockFoldService } from "@/lib/editor/codemirrorSqlBlockFolding";
 import { focusEditorView } from "@/lib/editor/queryEditorFocus";
@@ -6059,6 +6060,7 @@ onMounted(async () => {
   const SQL_SEMANTIC_HIGHLIGHT_DEBOUNCE_MS = 100;
   const refreshSqlSemanticHighlightEffect = StateEffect.define<null>();
   buildSqlSemanticHighlightExtension = () => [
+    createSqlAliasHighlights({ databaseType: props.databaseType, dialect: sqlBehaviorDialect(), enabled: queryEditorSelectionLanguage() === "sql" }),
     ViewPlugin.fromClass(
       class {
         decorations: import("@codemirror/view").DecorationSet;
diff --git a/apps/desktop/src/lib/__tests__/sql/semantic/aliasHighlights.spec.ts b/apps/desktop/src/lib/__tests__/sql/semantic/aliasHighlights.spec.ts
new file mode 100644
index 0000000000..83f960f193
--- /dev/null
+++ b/apps/desktop/src/lib/__tests__/sql/semantic/aliasHighlights.spec.ts
@@ -0,0 +1,162 @@
+import { describe, expect, it } from "vitest";
+import { sqlAliasHighlightGroups, type SqlAliasHighlightGroup } from "@/lib/sql/semantic/aliasHighlights";
+
+function spanTexts(sql: string, spans: Array<{ start: number; end: number }>): string[] {
+  return spans.map((span) => sql.slice(span.start, span.end));
+}
+
+function groupByDeclaration(sql: string, groups: SqlAliasHighlightGroup[]): Map<string, SqlAliasHighlightGroup> {
+  return new Map(groups.map((group) => [sql.slice(group.declaration.start, group.declaration.end), group]));
+}
+
+describe("sqlAliasHighlightGroups", () => {
+  it("highlights an alias declaration, qualifiers, and qualified references", () => {
+    const sql = "SELECT u.id, o.amount FROM users u JOIN orders o ON o.user_id = u.id";
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql));
+
+    expect(spanTexts(sql, [groups.get("u")!.declaration])).toEqual(["u"]);
+    expect(spanTexts(sql, groups.get("u")!.qualifiers)).toEqual(["u", "u"]);
+    expect(spanTexts(sql, groups.get("u")!.references)).toEqual(["u.id", "u.id"]);
+    expect(spanTexts(sql, groups.get("o")!.qualifiers)).toEqual(["o", "o"]);
+    expect(spanTexts(sql, groups.get("o")!.references)).toEqual(["o.amount", "o.user_id"]);
+  });
+
+  it("keeps a star column inside the reference span", () => {
+    const sql = "SELECT u.* FROM users u";
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql));
+
+    expect(spanTexts(sql, groups.get("u")!.references)).toEqual(["u.*"]);
+  });
+
+  it("still returns an unreferenced alias so its declaration can highlight itself", () => {
+    const sql = "SELECT id FROM users u";
+    const groups = sqlAliasHighlightGroups(sql);
+
+    expect(groups).toHaveLength(1);
+    expect(spanTexts(sql, [groups[0].declaration])).toEqual(["u"]);
+    expect(groups[0].qualifiers).toEqual([]);
+    expect(groups[0].references).toEqual([]);
+  });
+
+  it("mixes referenced and unreferenced aliases without dropping either", () => {
+    const sql = "SELECT u.id FROM users u, audit_log a";
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql));
+
+    expect(spanTexts(sql, groups.get("u")!.references)).toEqual(["u.id"]);
+    expect(groups.get("a")!.references).toEqual([]);
+  });
+
+  it("drops duplicate alias declarations that would produce no spans at all", () => {
+    const sql = "SELECT u.id FROM users u, logs u";
+    const groups = sqlAliasHighlightGroups(sql);
+
+    expect(groups).toEqual([]);
+  });
+
+  it("does not mistake schema.table.column or table function calls for alias references", () => {
+    const sql = "SELECT db.users.id FROM db.users";
+    const groups = sqlAliasHighlightGroups(sql);
+
+    expect(groups).toEqual([]);
+  });
+
+  it("resolves inner alias references to the shadowing subquery block", () => {
+    const sql = "SELECT * FROM users u WHERE u.id IN (SELECT ur.role FROM user_roles ur)";
+    const groups = sqlAliasHighlightGroups(sql);
+
+    expect(groups).toHaveLength(2);
+    expect(
+      spanTexts(
+        sql,
+        groups.map((group) => group.declaration),
+      ),
+    ).toEqual(["u", "ur"]);
+    expect(spanTexts(sql, groups[0].references)).toEqual(["u.id"]);
+    expect(spanTexts(sql, groups[1].references)).toEqual(["ur.role"]);
+  });
+
+  it("shadows an outer alias reused as the inner subquery alias", () => {
+    const sql = "SELECT * FROM users u WHERE u.id IN (SELECT u.role FROM user_roles u)";
+    const groups = sqlAliasHighlightGroups(sql);
+
+    expect(groups).toHaveLength(2);
+    expect(
+      spanTexts(
+        sql,
+        groups.map((group) => group.declaration),
+      ),
+    ).toEqual(["u", "u"]);
+    expect(spanTexts(sql, groups[0].references)).toEqual(["u.id"]);
+    expect(spanTexts(sql, groups[1].references)).toEqual(["u.role"]);
+  });
+
+  it("scopes grouped join sources and their group alias separately", () => {
+    const sql = "SELECT g.id FROM (users a JOIN orders b ON a.user_id = b.id) g WHERE g.amount > 0";
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql));
+
+    expect(spanTexts(sql, groups.get("a")!.references)).toEqual(["a.user_id"]);
+    expect(spanTexts(sql, groups.get("b")!.references)).toEqual(["b.id"]);
+    expect(spanTexts(sql, groups.get("g")!.qualifiers)).toEqual(["g", "g"]);
+    expect(spanTexts(sql, groups.get("g")!.references)).toEqual(["g.id", "g.amount"]);
+  });
+
+  it("keeps an unaliased parenthesized join transparent to the enclosing scope", () => {
+    const sql = "SELECT a.id FROM (users a JOIN orders b ON a.user_id = b.id)";
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql));
+
+    expect(spanTexts(sql, groups.get("a")!.references)).toEqual(["a.id", "a.user_id"]);
+    expect(spanTexts(sql, groups.get("b")!.references)).toEqual(["b.id"]);
+  });
+
+  it.each([
+    ["unbalanced open parenthesis", "SELECT * FROM (SELECT * FROM users u"],
+    ["stray close parenthesis", "SELECT * FROM users u) WHERE u.id > 0"],
+    ["unclosed string literal", "SELECT u.id FROM users u WHERE u.name = 'oops"],
+    ["unclosed mysql backtick identifier", "SELECT `e`.id FROM users `e"],
+    ["truncated before alias", "SELECT u.id FROM users"],
+    ["empty statement", ""],
+  ] as const)("returns no groups for a %s", (_label, sql) => {
+    expect(sqlAliasHighlightGroups(sql, { databaseType: "mysql" })).toEqual([]);
+  });
+
+  it("matches mysql backtick-quoted aliases and references", () => {
+    const sql = "SELECT `e`.id FROM `analytics`.`events` `e`";
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql, { databaseType: "mysql" }));
+
+    expect(spanTexts(sql, [groups.get("`e`")!.declaration])).toEqual(["`e`"]);
+    expect(spanTexts(sql, groups.get("`e`")!.references)).toEqual(["`e`.id"]);
+  });
+
+  it("treats mysql double quotes as strings, not alias qualifiers", () => {
+    const sql = 'SELECT "e".id FROM users e';
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql, { databaseType: "mysql" }));
+
+    expect(groups.get("e")!.references).toEqual([]);
+  });
+
+  it("matches sqlite double-quoted aliases and references", () => {
+    const sql = 'SELECT "u".id FROM users AS "u"';
+    const groups = groupByDeclaration(sql, sqlAliasHighlightGroups(sql, { databaseType: "sqlite" }));
+
+    expect(spanTexts(sql, [groups.get('"u"')!.declaration])).toEqual(['"u"']);
+    expect(spanTexts(sql, groups.get('"u"')!.references)).toEqual(['"u".id']);
+  });
+
+  it.each([
+    ["mysql unquoted alias", { databaseType: "mysql" }, "SELECT u.id FROM users U", true],
+    ["mysql backtick alias with different case", { databaseType: "mysql" }, "SELECT `e`.id FROM users `E`", true],
+    ["sql server unquoted alias", { databaseType: "sqlserver" }, "SELECT u.id FROM users U", true],
+    ["sql server bracket alias", { databaseType: "sqlserver" }, "SELECT [u].id FROM users [U]", true],
+    ["sqlite ascii fold", { databaseType: "sqlite" }, "SELECT U.id FROM users u", true],
+    ["postgres folds unquoted identifiers", { databaseType: "postgres" }, "SELECT u.id FROM users U", true],
+    ["postgres quoted alias keeps its case", { databaseType: "postgres" }, 'SELECT u.id FROM users "U"', false],
+    ["oracle folds unquoted identifiers up", { databaseType: "oracle" }, "SELECT U.ID FROM users u", true],
+    ["oracle quoted alias keeps its case", { databaseType: "oracle" }, 'SELECT u.id FROM users "u"', false],
+    ["generic dialect stays case-sensitive", {}, "SELECT u.id FROM users U", false],
+  ] as const)("resolves %s case handling", (_label, options, sql, matches) => {
+    const groups = sqlAliasHighlightGroups(sql, options);
+    const withReferences = groups.filter((group) => group.references.length > 0);
+
+    expect(withReferences).toHaveLength(matches ? 1 : 0);
+  });
+});
diff --git a/apps/desktop/src/lib/editor/codemirrorSqlAliasHighlights.ts b/apps/desktop/src/lib/editor/codemirrorSqlAliasHighlights.ts
new file mode 100644
index 0000000000..ee70b73605
--- /dev/null
+++ b/apps/desktop/src/lib/editor/codemirrorSqlAliasHighlights.ts
@@ -0,0 +1,96 @@
+import { StateEffect, type Extension, type Text } from "@codemirror/state";
+import { Decoration, EditorView, ViewPlugin, type DecorationSet, type ViewUpdate } from "@codemirror/view";
+import { MAX_ALIAS_HIGHLIGHT_SQL_LENGTH, sqlAliasHighlightGroups, type SqlAliasHighlightGroup } from "@/lib/sql/semantic/aliasHighlights";
+import { sqlSemanticDialectFor } from "@/lib/sql/semantic/dialect";
+import { resolveSqlStatementWindow, resolveStatementWindowFromSyntaxTree } from "@/lib/sql/sqlSyntaxTreeWindow";
+import type { SqlSemanticBuildOptions } from "@/lib/sql/semantic/types";
+
+const refreshAliasHighlights = StateEffect.define<null>();
+const aliasMark = Decoration.mark({ class: "cm-sqlAliasHighlight" });
+
+export function createSqlAliasHighlights(options: SqlSemanticBuildOptions & { enabled: boolean }): Extension {
+  if (!options.enabled) return [];
+  return [
+    ViewPlugin.fromClass(
+      class {
+        decorations: DecorationSet = Decoration.none;
+        private timer: ReturnType<typeof setTimeout> | null = null;
+        private doc: Text | null = null;
+        private sql = "";
+        private window: { from: number; to: number } | null = null;
+        private groups: SqlAliasHighlightGroup[] = [];
+
+        constructor(view: EditorView) {
+          this.schedule(view);
+        }
+
+        update(update: ViewUpdate) {
+          if (update.docChanged || update.selectionSet || update.focusChanged) {
+            this.decorations = Decoration.none;
+            this.schedule(update.view);
+          } else if (update.transactions.some((transaction) => transaction.effects.some((effect) => effect.is(refreshAliasHighlights)))) {
+            this.render(update.view);
+          } else if (update.viewportChanged) {
+            this.render(update.view);
+          }
+        }
+
+        destroy() {
+          if (this.timer !== null) clearTimeout(this.timer);
+        }
+
+        private schedule(view: EditorView) {
+          if (this.timer !== null) clearTimeout(this.timer);
+          this.timer = null;
+          if (!view.hasFocus || view.state.selection.ranges.length !== 1 || !view.state.selection.main.empty) return;
+          this.timer = setTimeout(() => {
+            this.timer = null;
+            view.dispatch({ effects: refreshAliasHighlights.of(null) });
+          }, 100);
+        }
+
+        private render(view: EditorView) {
+          const { state } = view;
+          this.decorations = Decoration.none;
+          if (this.timer !== null || !view.hasFocus || state.selection.ranges.length !== 1 || !state.selection.main.empty) return;
+          const cursor = state.selection.main.head;
+          if (this.doc !== state.doc) {
+            this.doc = state.doc;
+            this.sql = "";
+            this.window = null;
+          }
+          if (!this.window || cursor < this.window.from || cursor >= this.window.to) {
+            let window = resolveStatementWindowFromSyntaxTree(state, cursor);
+            if (!window) {
+              // Avoid flattening huge documents while the incremental parser is still catching up.
+              if (state.doc.length > MAX_ALIAS_HIGHLIGHT_SQL_LENGTH) return;
+              this.sql ||= state.doc.toString();
+              window = resolveSqlStatementWindow(this.sql, cursor, state, sqlSemanticDialectFor(options).id);
+            }
+            this.window = window;
+            this.groups = window.to - window.from <= MAX_ALIAS_HIGHLIGHT_SQL_LENGTH ? sqlAliasHighlightGroups(state.doc.sliceString(window.from, window.to), options) : [];
+          }
+          const offset = this.window.from;
+          const localCursor = cursor - offset;
+          const containsCursor = (span: { start: number; end: number }) => span.start <= localCursor && localCursor <= span.end;
+          const group = this.groups.find((candidate) => containsCursor(candidate.declaration) || candidate.qualifiers.some(containsCursor));
+          if (!group) return;
+          const ranges = [group.declaration, ...group.references].filter((span) => view.visibleRanges.some((visible) => span.end + offset > visible.from && span.start + offset < visible.to)).map((span) => aliasMark.range(span.start + offset, span.end + offset));
+          this.decorations = Decoration.set(ranges, true);
+        }
+      },
+      { decorations: (plugin) => plugin.decorations },
+    ),
+    EditorView.baseTheme({
+      ".cm-sqlAliasHighlight": {
+        backgroundColor: "rgb(34 139 74 / 0.16)",
+        boxShadow: "inset 0 0 0 1px rgb(34 139 74 / 0.28)",
+        borderRadius: "2px",
+      },
+      "&dark .cm-sqlAliasHighlight": {
+        backgroundColor: "rgb(110 231 183 / 0.18)",
+        boxShadow: "inset 0 0 0 1px rgb(110 231 183 / 0.32)",
+      },
+    }),
+  ];
+}
diff --git a/apps/desktop/src/lib/sql/semantic/aliasHighlights.ts b/apps/desktop/src/lib/sql/semantic/aliasHighlights.ts
new file mode 100644
index 0000000000..bd8d519917
--- /dev/null
+++ b/apps/desktop/src/lib/sql/semantic/aliasHighlights.ts
@@ -0,0 +1,138 @@
+import { sqlSemanticDialectFor } from "@/lib/sql/semantic/dialect";
+import { sqlSemanticQueryBlockSources, type SqlSemanticGroupedSourceScope } from "@/lib/sql/semantic/model";
+import { tokenizeSqlSemantic, tokenIsIdentifier, unquoteSqlSemanticIdentifier } from "@/lib/sql/semantic/tokens";
+import type { SqlSemanticBuildOptions, SqlSemanticSpan, SqlSemanticToken } from "@/lib/sql/semantic/types";
+
+export interface SqlAliasHighlightGroup {
+  declaration: SqlSemanticSpan;
+  qualifiers: SqlSemanticSpan[];
+  references: SqlSemanticSpan[];
+}
+
+interface QueryBlock {
+  start: number;
+  end: number;
+  depth: number;
+  parent?: QueryBlock;
+  aliases: Map<string, SqlAliasHighlightGroup | null>;
+  sources: SqlSemanticSpan[];
+}
+
+const SET_OPERATORS = new Set(["union", "intersect", "except"]);
+// MySQL aliases and SQL Server default collations compare identifiers case-insensitively.
+const CASE_INSENSITIVE_ALIAS_DIALECTS = new Set(["mysql", "sqlserver", "sqlite"]);
+export const MAX_ALIAS_HIGHLIGHT_SQL_LENGTH = 128 * 1024;
+
+function lastBlock(blocks: QueryBlock[], predicate: (block: QueryBlock) => boolean): QueryBlock | undefined {
+  for (let index = blocks.length - 1; index >= 0; index--) {
+    if (predicate(blocks[index])) return blocks[index];
+  }
+  return undefined;
+}
+
+/** Input is a single statement; all returned spans are relative to that statement. */
+export function sqlAliasHighlightGroups(sql: string, options: SqlSemanticBuildOptions = {}): SqlAliasHighlightGroup[] {
+  if (sql.length > MAX_ALIAS_HIGHLIGHT_SQL_LENGTH) return [];
+  const dialect = sqlSemanticDialectFor(options);
+  const allTokens = tokenizeSqlSemantic(sql, dialect.id, {
+    mysqlDashCommentRequiresWhitespace: dialect.id === "mysql",
+    mysqlBackslashEscape: dialect.id === "mysql",
+    mysqlDoubleQuoteIsString: dialect.id === "mysql",
+  });
+  if (allTokens.some((token) => token.closed === false)) return [];
+  const tokens = allTokens.filter((token) => token.kind !== "comment");
+  if (tokens.length > 20_000) return [];
+  let parentheses = 0;
+  for (const token of tokens) {
+    if (token.text === "(") parentheses++;
+    if (token.text === ")" && --parentheses < 0) return [];
+  }
+  if (parentheses !== 0) return [];
+  const tokensByStart = new Map(tokens.map((token) => [token.span.start, token]));
+  const nameOf = (token: SqlSemanticToken) => {
+    const name = dialect.normalizeIdentifier(unquoteSqlSemanticIdentifier(token), token.kind === "quoted_identifier");
+    // These dialects compare even quoted identifiers case-insensitively for ASCII letters.
+    // Keep the spelling normalizer unchanged, and preserve other dialects' quote and case semantics.
+    return CASE_INSENSITIVE_ALIAS_DIALECTS.has(dialect.id) ? name.replace(/[A-Z]/g, (letter) => letter.toLowerCase()) : name;
+  };
+  const blocks: QueryBlock[] = [];
+  const groups: SqlAliasHighlightGroup[] = [];
+
+  for (let index = 0; index < tokens.length; index++) {
+    const token = tokens[index];
+    if (token.kind !== "word" || token.normalized !== "select") continue;
+    if (blocks.length >= 128) return [];
+    let end = index + 1;
+    while (end < tokens.length) {
+      const next = tokens[end];
+      if (next.depth < token.depth || next.text === ";" || (next.depth === token.depth && next.kind === "word" && SET_OPERATORS.has(next.normalized))) break;
+      end++;
+    }
+    const groupedScopes: SqlSemanticGroupedSourceScope[] = [];
+    const sources = sqlSemanticQueryBlockSources(tokens.slice(index, end), options, groupedScopes);
+    const scopes = [
+      { start: index, end, depth: token.depth, sources },
+      ...groupedScopes.map((scope) => ({
+        start: tokens.findIndex((candidate) => candidate.span.start >= scope.span.start),
+        end: tokens.findIndex((candidate) => candidate.span.start >= scope.span.end),
+        depth: scope.depth,
+        sources: scope.sources,
+      })),
+    ];
+    for (const scope of scopes) {
+      if (scope.start < 0 || scope.end <= scope.start) continue;
+      if (blocks.length >= 128) return [];
+      const block: QueryBlock = { start: scope.start, end: scope.end, depth: scope.depth, aliases: new Map(), sources: [] };
+      for (const source of scope.sources) {
+        // Only exclude the source name itself; table-function arguments can reference aliases.
+        if (source.qualifiedName) block.sources.push(source.qualifiedName.span);
+        if (!source.aliasSpan) {
+          // An unaliased local table also hides an outer alias with the same name.
+          const parts = source.qualifiedName?.parts;
+          const localName = parts?.[parts.length - 1];
+          const localToken = localName && tokensByStart.get(localName.span.start);
+          if (localToken) block.aliases.set(nameOf(localToken), null);
+          continue;
+        }
+        const declaration = tokensByStart.get(source.aliasSpan.start);
+        if (!declaration) continue;
+        const key = nameOf(declaration);
+        const group: SqlAliasHighlightGroup = { declaration: source.aliasSpan, qualifiers: [], references: [] };
+        if (block.aliases.has(key)) block.aliases.set(key, null);
+        else block.aliases.set(key, group);
+      }
+      blocks.push(block);
+    }
+  }
+
+  // Group scopes can be discovered before their nested SELECTs. Establish containment only
+  // after collecting all scopes so inner names never leak into the enclosing query.
+  blocks.sort((left, right) => left.start - right.start || right.end - left.end);
+  for (let index = 0; index < blocks.length; index++) {
+    const block = blocks[index];
+    block.parent = lastBlock(blocks.slice(0, index), (candidate) => candidate.depth < block.depth && candidate.start <= block.start && candidate.end >= block.end);
+  }
+
+  for (let index = 0; index + 2 < tokens.length; index++) {
+    const qualifier = tokens[index];
+    const column = tokens[index + 2];
+    if (!tokenIsIdentifier(qualifier) || tokens[index + 1].text !== "." || (column.text !== "*" && !tokenIsIdentifier(column))) continue;
+    // Do not mistake schema.table.column or a qualified function call for alias.column.
+    if (tokens[index - 1]?.text === "." || tokens[index + 3]?.text === "." || tokens[index + 3]?.text === "(") continue;
+    const block = lastBlock(blocks, (candidate) => candidate.start <= index && index < candidate.end);
+    if (!block || block.sources.some((span) => span.start <= qualifier.span.start && column.span.end <= span.end)) continue;
+    const key = nameOf(qualifier);
+    let owner: QueryBlock | undefined = block;
+    while (owner && !owner.aliases.has(key)) owner = owner.parent;
+    const group = owner?.aliases.get(key);
+    if (!group) continue;
+    group.qualifiers.push(qualifier.span);
+    group.references.push({ start: qualifier.span.start, end: column.span.end });
+  }
+  for (const block of blocks) {
+    // Keep unreferenced declarations too: the caller still highlights the declaration itself
+    // when the cursor sits on it. Only shadowed (null) entries produce no spans at all.
+    for (const group of block.aliases.values()) if (group) groups.push(group);
+  }
+  return groups;
+}
diff --git a/apps/desktop/src/lib/sql/semantic/model.ts b/apps/desktop/src/lib/sql/semantic/model.ts
index 816c2661fb..408f84707e 100644
--- a/apps/desktop/src/lib/sql/semantic/model.ts
+++ b/apps/desktop/src/lib/sql/semantic/model.ts
@@ -34,6 +34,14 @@ interface ParseState {
   tokens: SqlSemanticToken[];
   statement: SqlSemanticStatement;
   cteSources: SqlSemanticRowSource[];
+  expandGroupedSources?: boolean;
+  groupedSourceScopes?: SqlSemanticGroupedSourceScope[];
+}
+
+export interface SqlSemanticGroupedSourceScope {
+  span: SqlSemanticSpan;
+  depth: number;
+  sources: SqlSemanticRowSource[];
 }
 
 interface QuerySourceRange {
@@ -437,6 +445,25 @@ function parseRowSource(state: ParseState, target: number, introducer: string, s
   return parseTableFunctionSource(state, target, introducer, sourceIndex) ?? parseTableSource(state, target, introducer, sourceIndex);
 }
 
+function parseRowSourceList(state: ParseState, target: number, introducer: string, sourceIndex: number): { sources: SqlSemanticRowSource[]; nextIndex: number } | null {
+  const open = state.tokens[target];
+  if (state.expandGroupedSources && open?.text === "(" && open.depth < 128) {
+    const close = findMatchingParenToken(state.tokens, target);
+    const first = state.tokens[target + 1];
+    const isQuery = first?.kind === "word" && (first.normalized === "select" || first.normalized === "with");
+    if (close >= 0 && !isQuery) {
+      // An unaliased parenthesized join is transparent to the surrounding query scope.
+      // A SELECT body or an explicitly aliased group must retain its own boundary.
+      const from: SqlSemanticToken = { ...open, kind: "word", text: "from", normalized: "from", depth: open.depth + 1 };
+      const sources = parseRowSourcesAtDepth({ ...state, tokens: [from, ...state.tokens.slice(target + 1, close)] }, from.depth, sourceIndex);
+      if (!aliasAfter(state.tokens, close + 1, state.dialect).alias) return { sources, nextIndex: close + 1 };
+      state.groupedSourceScopes?.push({ span: { start: open.span.end, end: state.tokens[close].span.start }, depth: from.depth, sources });
+    }
+  }
+  const parsed = parseRowSource(state, target, introducer, sourceIndex);
+  return parsed ? { sources: [parsed.source], nextIndex: parsed.nextIndex } : null;
+}
+
 function parseRowSourcesAtDepth(state: ParseState, sourceDepth: number, sourceIndexOffset = 0): SqlSemanticRowSource[] {
   const sources: SqlSemanticRowSource[] = [];
   let inSelectFromClause = false;
@@ -449,9 +476,9 @@ function parseRowSourcesAtDepth(state: ParseState, sourceDepth: number, sourceIn
       else if (inSelectFromClause && FROM_CLAUSE_BOUNDARIES.has(item.normalized)) inSelectFromClause = false;
     }
     if (inSelectFromClause && item.text === ",") {
-      const parsed = parseRowSource(state, index + 1, "from", sourceIndexOffset + sources.length);
+      const parsed = parseRowSourceList(state, index + 1, "from", sourceIndexOffset + sources.length);
       if (parsed) {
-        sources.push(parsed.source);
+        sources.push(...parsed.sources);
         index = parsed.nextIndex - 1;
       }
       continue;
@@ -465,9 +492,9 @@ function parseRowSourcesAtDepth(state: ParseState, sourceDepth: number, sourceIn
     while (JOIN_MODIFIERS.has(state.tokens[target]?.normalized ?? "")) target += 1;
     target = sqlServerMaintenanceTableTarget(state.tokens, target, normalized, state.dialect);
     for (;;) {
-      const parsed = parseRowSource(state, target, normalized, sourceIndexOffset + sources.length);
+      const parsed = parseRowSourceList(state, target, normalized, sourceIndexOffset + sources.length);
       if (!parsed) break;
-      sources.push(parsed.source);
+      sources.push(...parsed.sources);
       index = parsed.nextIndex - 1;
 
       const separator = state.tokens[parsed.nextIndex];
@@ -478,6 +505,17 @@ function parseRowSourcesAtDepth(state: ParseState, sourceDepth: number, sourceIn
   return dedupeSources(sources);
 }
 
+/** Parse declarations in one query block without merging outer or sibling sources. */
+export function sqlSemanticQueryBlockSources(tokens: SqlSemanticToken[], options: SqlSemanticBuildOptions = {}, groupedSourceScopes?: SqlSemanticGroupedSourceScope[]): SqlSemanticRowSource[] {
+  if (!tokens.length) return [];
+  const statement: SqlSemanticStatement = {
+    kind: statementKind(tokens),
+    span: { start: tokens[0].span.start, end: tokens[tokens.length - 1].span.end },
+    text: "",
+  };
+  return parseRowSourcesAtDepth({ dialect: sqlSemanticDialectFor(options), tokens, statement, cteSources: [], expandGroupedSources: true, groupedSourceScopes }, tokens[0].depth);
+}
+
 function querySourceRanges(tokens: readonly SqlSemanticToken[], cursor: number): QuerySourceRange[] {
   const rootDepth = tokens.reduce((min, item) => Math.min(min, item.depth), Number.POSITIVE_INFINITY);
   const fallbackDepth = Number.isFinite(rootDepth) ? rootDepth : 0;