🐛 fix(duckdb): 修复唯一索引识别与多库对象解析

- 合并 DuckDB 约束与索引元数据，恢复唯一索引表的可编辑判定
- 修复 attach 多库场景下 catalog/schema/table 定位混乱问题
- 统一前后端 qualified name 解析，支持带点和带引号对象名
- 补充 DuckDB 元数据与编辑链路回归测试

frontend/src/utils/qualifiedName.ts

@@ -0,0 +1,126 @@
+export type QualifiedNameParts = {
+  parentPath: string;
+  objectName: string;
+};
+
+const normalizeIdentifierEscapes = (raw: string): string => {
+  let value = String(raw || '').trim();
+  for (let i = 0; i < 4; i += 1) {
+    const next = String(value || '').trim()
+      .replace(/\\\\"/g, '\\"')
+      .replace(/\\"/g, '"');
+    if (next === value) break;
+    value = next;
+  }
+  return String(value || '').trim();
+};
+
+export const stripIdentifierQuotes = (part: string): string => {
+  const text = normalizeIdentifierEscapes(part);
+  if (!text) return '';
+  if (text.length >= 2) {
+    const first = text[0];
+    const last = text[text.length - 1];
+    if (first === '"' && last === '"') {
+      return text.slice(1, -1).replace(/""/g, '"').trim();
+    }
+    if (first === '`' && last === '`') {
+      return text.slice(1, -1).replace(/``/g, '`').trim();
+    }
+    if (first === '[' && last === ']') {
+      return text.slice(1, -1).replace(/]]/g, ']').trim();
+    }
+  }
+  return text;
+};
+
+export const splitQualifiedNameSegments = (qualifiedName: string): string[] => {
+  const text = normalizeIdentifierEscapes(qualifiedName);
+  if (!text) return [];
+
+  const segments: string[] = [];
+  let current = '';
+  let inDouble = false;
+  let inBacktick = false;
+  let inBracket = false;
+
+  const flush = () => {
+    const value = current.trim();
+    current = '';
+    if (!value) return;
+    segments.push(stripIdentifierQuotes(value));
+  };
+
+  for (let i = 0; i < text.length; i += 1) {
+    const ch = text[i];
+
+    if (inDouble) {
+      current += ch;
+      if (ch === '"' && text[i + 1] === '"') {
+        current += text[i + 1];
+        i += 1;
+        continue;
+      }
+      if (ch === '"') inDouble = false;
+      continue;
+    }
+
+    if (inBacktick) {
+      current += ch;
+      if (ch === '`' && text[i + 1] === '`') {
+        current += text[i + 1];
+        i += 1;
+        continue;
+      }
+      if (ch === '`') inBacktick = false;
+      continue;
+    }
+
+    if (inBracket) {
+      current += ch;
+      if (ch === ']' && text[i + 1] === ']') {
+        current += text[i + 1];
+        i += 1;
+        continue;
+      }
+      if (ch === ']') inBracket = false;
+      continue;
+    }
+
+    if (ch === '"') {
+      inDouble = true;
+      current += ch;
+      continue;
+    }
+    if (ch === '`') {
+      inBacktick = true;
+      current += ch;
+      continue;
+    }
+    if (ch === '[') {
+      inBracket = true;
+      current += ch;
+      continue;
+    }
+    if (ch === '.') {
+      flush();
+      continue;
+    }
+    current += ch;
+  }
+
+  flush();
+  return segments;
+};
+
+export const splitQualifiedName = (qualifiedName: string): QualifiedNameParts => {
+  const segments = splitQualifiedNameSegments(qualifiedName);
+  if (segments.length === 0) return { parentPath: '', objectName: '' };
+  if (segments.length === 1) return { parentPath: '', objectName: segments[0] };
+  return {
+    parentPath: segments.slice(0, -1).join('.'),
+    objectName: segments[segments.length - 1],
+  };
+};
+
+export const splitQualifiedNameLast = splitQualifiedName;

frontend/src/utils/sidebarMetadata.ts

@@ -1,17 +1,5 @@
 import { normalizeOceanBaseProtocol } from './oceanBaseProtocol';
-
-const splitQualifiedName = (qualifiedName: string): { schemaName: string; objectName: string } => {
-  const raw = String(qualifiedName || '').trim();
-  if (!raw) return { schemaName: '', objectName: '' };
-  const idx = raw.lastIndexOf('.');
-  if (idx <= 0 || idx >= raw.length - 1) {
-    return { schemaName: '', objectName: raw };
-  }
-  return {
-    schemaName: raw.substring(0, idx),
-    objectName: raw.substring(idx + 1),
-  };
-};
+import { splitQualifiedNameLast } from './qualifiedName';
 
 const normalizeSidebarConnectionDialect = (type: string, driver: string, oceanBaseProtocol?: string): string => {
   const normalizedType = String(type || '').trim().toLowerCase();
@@ -45,7 +33,7 @@ export const normalizeSidebarViewName = (dialect: string, dbName: string, schema
   }
 
   if (normalizedDialect === 'mysql') {
-    const parsed = splitQualifiedName(normalizedViewName);
+    const parsed = splitQualifiedNameLast(normalizedViewName);
     if (parsed.objectName) {
       return parsed.objectName;
     }

frontend/src/utils/sql.test.ts

@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest';
 
-import { buildOrderBySQL, buildPaginatedSelectSQL, reverseOrderBySQL } from './sql';
+import { buildOrderBySQL, buildPaginatedSelectSQL, quoteQualifiedIdent, reverseOrderBySQL } from './sql';
 
 describe('buildOrderBySQL', () => {
   it('does not add fallback ORDER BY for DuckDB without explicit sort', () => {
@@ -52,3 +52,15 @@ describe('reverseOrderBySQL', () => {
       .toBe(' ORDER BY COALESCE([a], [b]) DESC, [id] ASC');
   });
 });
+
+describe('quoteQualifiedIdent', () => {
+  it('does not split dots inside quoted DuckDB identifiers', () => {
+    expect(quoteQualifiedIdent('duckdb', '"daily.events"."2026.06"'))
+      .toBe('"daily.events"."2026.06"');
+  });
+
+  it('preserves three-part DuckDB names with quoted dots', () => {
+    expect(quoteQualifiedIdent('duckdb', '"analytics.catalog"."main.schema"."daily.events"'))
+      .toBe('"analytics.catalog"."main.schema"."daily.events"');
+  });
+});

frontend/src/utils/sql.ts

@@ -1,3 +1,5 @@
+import { splitQualifiedNameSegments, stripIdentifierQuotes } from './qualifiedName';
+
 export type FilterCondition = {
   id?: number;
   enabled?: boolean;
@@ -8,17 +10,7 @@ export type FilterCondition = {
   value2?: string;
 };
 
-const normalizeIdentPart = (ident: string) => {
-  let raw = (ident || '').trim();
-  if (!raw) return raw;
-  const first = raw[0];
-  const last = raw[raw.length - 1];
-  if ((first === '"' && last === '"') || (first === '`' && last === '`')) {
-    raw = raw.slice(1, -1).trim();
-  }
-  raw = raw.replace(/["`]/g, '').trim();
-  return raw;
-};
+const normalizeIdentPart = (ident: string) => stripIdentifierQuotes(ident);
 
 // 检查标识符是否需要引号（包含特殊字符或是保留字）
 const needsQuote = (ident: string): boolean => {
@@ -62,9 +54,10 @@ export const quoteIdentPart = (dbType: string, ident: string) => {
 export const quoteQualifiedIdent = (dbType: string, ident: string) => {
   const raw = (ident || '').trim();
   if (!raw) return raw;
-  const parts = raw.split('.').map(normalizeIdentPart).filter(Boolean);
-  if (parts.length <= 1) return quoteIdentPart(dbType, raw);
-  return parts.map(p => quoteIdentPart(dbType, p)).join('.');
+  const parts = splitQualifiedNameSegments(raw).filter(Boolean);
+  if (parts.length === 0) return quoteIdentPart(dbType, raw);
+  if (parts.length === 1 && parts[0] === normalizeIdentPart(raw)) return quoteIdentPart(dbType, raw);
+  return parts.map((part) => quoteIdentPart(dbType, part)).join('.');
 };
 
 export const escapeLiteral = (val: string) => (val || '').replace(/'/g, "''");