release: v0.3.2 — 质量加固 + SQL扩展 + 表达式 + 并发同步

v0.2.6 质量加固:
- 修复 AriaEngine 二级索引 SSTable 互相覆盖(命名空间隔离)
- 修复 LSM 多版本读取顺序错误 + MergeIterator 取最新来源
- 重写 LZ4 压缩器(往返一致性 + 缓冲区溢出)
- sstableCache LRU 上限 + 预加载兜底(BufferPool 配置生效)
- 修复 React/Vue 集成 import type 运行时 bug + exports 子路径
- 新增 38 个测试(LZ4往返/Crypto/集成), 删除伪测试

v0.3.0 SQL 功能扩展:
- 多语句 parseAll + 事务语句 BEGIN/COMMIT/ROLLBACK
- INSERT INTO ... SELECT + UNION/UNION ALL + EXISTS 关联子查询
- CREATE/DROP INDEX 五引擎实现 + 别名 WHERE 修复
- benchmark 页面 + 36 个新测试

v0.3.1 表达式与性能:
- CASE WHEN 表达式(SELECT 列/WHERE/聚合)
- JOIN + 关联子查询逐行绑定
- WAL 批量组提交(写放大 O(N)→O(1))
- 修复 pending frozen 可见性 + flush 缓存竞争

v0.3.2 并发:
- CASE WHEN 用于 WHERE/聚合 + JOIN 哈希连接
- 多标签页同步(multiTabSync + BroadcastChannel)
- IndexedDB schema 持久化(reopen 后表结构恢复)
- 修复 where-matcher 顶层 $not
- 修复 CJS 产物 .js 被 ESM 解析(exports 空) — .cjs 后缀 + exports 修正
- 836 测试 / 44 套件 / 81.0% 覆盖率

src/engine/memory.ts

@@ -148,6 +148,41 @@ export class MemoryEngine implements IStorageEngine {
     if (tableIndexes) for (const colIndex of tableIndexes.values()) colIndex.clear();
   }
 
+  // ---- 动态索引（v0.3.0） ----
+
+  async createIndex(tableName: string, column: string, unique?: boolean): Promise<void> {
+    this.ensureTable(tableName);
+    const schema = this.schemas.get(tableName)!;
+    const colDef = schema.columns[column];
+    if (!colDef) throw new DatabaseError(`Column "${column}" does not exist in table "${tableName}"`, 'COLUMN_NOT_FOUND');
+    if (colDef.index || colDef.unique) return; // 已存在
+    colDef.index = true;
+    if (unique) colDef.unique = true;
+
+    const tableIndexes = this.indexes.get(tableName)!;
+    if (!tableIndexes.has(column)) tableIndexes.set(column, new Map());
+    const colIndex = tableIndexes.get(column)!;
+    const table = this.tables.get(tableName)!;
+    for (const [pk, row] of table) {
+      const value = row[column];
+      if (value !== undefined && value !== null) {
+        if (!colIndex.has(value)) colIndex.set(value, new Set());
+        colIndex.get(value)!.add(pk);
+      }
+    }
+  }
+
+  async dropIndex(tableName: string, column: string, _indexName?: string): Promise<void> {
+    this.ensureTable(tableName);
+    const schema = this.schemas.get(tableName)!;
+    const colDef = schema.columns[column];
+    if (!colDef) throw new DatabaseError(`Column "${column}" does not exist in table "${tableName}"`, 'COLUMN_NOT_FOUND');
+    colDef.index = false;
+    colDef.unique = false;
+    const tableIndexes = this.indexes.get(tableName);
+    if (tableIndexes) tableIndexes.delete(column);
+  }
+
   // ---- 事务 ----
 
   async beginTransaction(): Promise<void> {
@@ -297,10 +332,9 @@ export class MemoryEngine implements IStorageEngine {
       for (const [colName, colDef] of Object.entries(refSchema.columns)) {
         if (!colDef.references || !colDef.onDelete) continue;
 
-        const [refTable, refCol] = colDef.references.split('.');
+        const [refTable] = colDef.references.split('.');
         if (refTable !== tableName) continue;
 
-        const refPkCol = refCol;
         const refTableData = this.tables.get(refTableName);
         if (!refTableData) continue;