SQL 生成器

API 文档

抽象类

DbQuery 抽象类

class YourQuery extends DbQuery {
  execute(sql: QueryInput | MultipleQueryInput): Promise<void> {
    // implement
  }

  query<T extends MultipleQueryResult = MultipleQueryResult>(sql: MultipleQueryInput): Promise<T>;
  query<T = any>(sql: QueryDataInput<T>): Promise<QueryRowsResult<T>>;
  query<T = any>(sql: QueryInput): Promise<QueryRowsResult<T>>;
  query<T = any>(sql: QueryInput | MultipleQueryInput): Promise<QueryRowsResult<T>> {
    // implement
  }
  multipleQuery<T extends MultipleQueryResult = MultipleQueryResult>(sql: StringLike): Promise<T> {
    // implement
  }
  /**
   * 执行多语句的方法
   * @deprecated 不建议使用。改用 query()
   */
  abstract multipleQuery<T extends MultipleQueryResult = MultipleQueryResult>(sql: SqlLike | SqlLike[]): Promise<T>;
}
const db: DbQuery = new YourQuery();

declare const db: DbQuery;

type Row = { name: string; age: number };
const sqlText = "SELECT * FROM user";

const rows: Row[] = await db.queryRows<Row>(sqlText);
const count: number = await db.queryCount(sqlText);
const rows: Map<string, Row> = await db.queryMap<Row>(sqlText, "name");

DbQueryPool 抽象类

class YourPool extends DbQueryPool {
  // implement
}
const pool: DbQueryPool = new YourPool();

普通查询

const conn = await pool.connect();
try {
  await conn.queryRows(sqlText);
} finally {
  conn.release();
}

或者，使用 using 语法更优雅 (推荐)

using conn = await pool.connect();
await conn.queryRows(sqlText);

事务查询

const conn = pool.begin();
try {
  await conn.queryRows(sqlText);
  await conn.queryRows(sqlText);
  await conn.commit();
} catch (e) {
  await conn.rollback();
  throw e;
}

或者，使用 using 语法更优雅 (推荐)

await using conn = pool.begin();

await conn.queryRows(sqlText);
await conn.queryRows(sqlText);
await conn.commit();

游标查询

const cursor = await pool.cursor(sqlText);

let rows = await cursor.read(20);
while (rows.length) {
  console.log(rows);
  rows = await cursor.read(20);
  if (conditions) {
    await cursor.close(); // 提前关闭游标
    break;
  }
}

或者使用 for await of 更优雅 (推荐)

const cursor = await pool.cursor(sqlText);
for await (const element of cursor) {
  console.log(element);
  if (conditions) break; //提前关闭游标
}