tornado中使用pymssql创建sql server 连接池

在Tornado中使用pymssql创建SQL Server连接池可以通过以下步骤实现：

1. 首先，确保已经安装了pymssql库。可以使用pip命令进行安装：`pip install pymssql`

2. 导入必要的模块：

import pymssql
from tornado.ioloop import IOLoop
from tornado.gen import coroutine
from tornado.concurrent import Future

3. 创建一个连接池类，用于管理数据库连接：

class ConnectionPool:
    def __init__(self, host, user, password, database, max_connections=10):
        self.host = host
        self.user = user
        self.password = password
        self.database = database
        self.max_connections = max_connections
        self.connections = []

    def get_connection(self):
        if len(self.connections) < self.max_connections:
            conn = pymssql.connect(
                host=self.host,
                user=self.user,
                password=self.password,
                database=self.database
            )
            self.connections.append(conn)
            return conn
        else:
            raise Exception("Connection pool is full")

    def release_connection(self, conn):
        if conn in self.connections:
            self.connections.remove(conn)
            conn.close()

4. 在Tornado的请求处理器中使用连接池：

class MyHandler(RequestHandler):
    def initialize(self, connection_pool):
        self.connection_pool = connection_pool

    @coroutine
    def get(self):
        conn = self.connection_pool.get_connection()
        cursor = conn.cursor()
        cursor.execute("SELECT * FROM table_name")
        result = cursor.fetchall()
        cursor.close()
        self.connection_pool.release_connection(conn)
        
        # 处理查询结果
        # ...

5. 创建连接池实例并启动Tornado应用：

if __name__ == "__main__":
    connection_pool = ConnectionPool(host="localhost", user="username", password="password", database="dbname")
    app = Application([
        (r"/", MyHandler, dict(connection_pool=connection_pool)),
    ])
    app.listen(8888)
    IOLoop.current().start()

这样，你就可以在Tornado应用中使用pymssql创建SQL Server连接池了。