How to use pg-promise?

I have a scenario in which i have used 'async' library in a manner as below

> async.series([function (cb){
 // first function
},function (cb){
  async.parallel([function (cbP){
     async.eachSeries(xseries, function (x, cbX){
       //Some Function
     }, function (err){

     });
  }], function (err){
    cb();
  }
}

How can I implement it using pg-promise functions ?

via Lakshmipriya Mukundan