var mysql = Meteor.npmRequire('mysql');

var  querySync;
var connection;
var failed=false;

Meteor.startup(function(){connection = mysql.createConnection('数据库url');function doMysql(connection,sqlStr , cb){connection.query(sqlStr , cb);}querySync = Async.wrap(doMysql);}
);

Meteor.methods({"querySqlEcho" : function(sqlStr){try{if(failed||connection===undefined){connection = mysql.createConnection(‘数据库url’);}var response = querySync(connection,sqlStr);

        failed=false;

 return response; } catch(e){

        failed=true;

 return null; } } });