Query to get child table data using parent rowid sqlite in ionic 3

So my problem is how can I get all the data from the child table using the rowid of my parent table , problem here is after query the 1st row id I can see an output but then the next rowid will say

undefined is not an object (evaluating ‘res.rows.item(z)’)

here is my code

console.log("Reloading all data");
  name: 'ionicdb.db',
  location: 'default'
}).then((db: SQLiteObject) =>{
  db.executeSql('SELECT * FROM carrots_expenses', {})
  .then(res => {
    console.log("Selecting all data executed! : ");
    if(res.rows.length > 0){
      for(let z=0; z < res.rows.length; z++){
        console.log("Fetch id from carrots expenses : " +res.rows.item(z).rowid);
        console.log("Parent ID : " +this.parent_id[z]);
        db.executeSql('SELECT * FROM carrots_calculated_values WHERE rowid = '+this.parent_id[z],{})
        .then(res => {
        console.log("Fetch data from carrots_calculated_values");
        this.dataRecord.push({id: res.rows.item(0).rowid ,cost: res.rows.item(0).cost_total , gain: res.rows.item(0).gain_total , money_return: res.rows.item(0).money_return , expected_Kilo: res.rows.item(0).expected_Kilo, expected_Price: res.rows.item(0).expected_Price});
        console.log("Row id : " +res.rows.item(0).rowid+ " Cost : " +res.rows.item(0).gain_total);
        }).catch(e=> console.log(e.message));
      }).catch(e=> console.log(e.message));
  }).catch(e=> console.log(e.message));}

Where did I miss? or maybe suggestion on how to do it wisely

IONIC CLI V : 3.20.0
Sqlite cli v :5.6.0