How to write javascript code calculate sum of specific column rows data between first and last row?

Hi @RM12 ,

One way to fulfill this business requirement you can refer:

1. Suppose you have create a service to get the needed query result of this database table to a infotable parameter named tableResult which include 2 columns(heartRange and timestamp);

2. Create a new infotable through a service which will derived one number field for caculating

var tableResult=me.tableResult;
var params = {
types : "NUMBER",
columns : "number", 
t : tableResult,
expressions : "1"
};
// DeriveFields
var result = Resources['InfoTableFunctions'].DeriveFields(params);

3. Create a datashape contains 3 fields - heartRange, timestamp, number 

4. Create a service to caculate:

var tr = me.tableResult();
var st=Date.parse(StartTime); //inputparameter
var et=Date.parse(EndTime); //inputparameter
var params = {
 infoTableName : "queryHeartRange",
 dataShapeName : "queryHeartRangeDatashape"
};
var queryHeartRange = Resources["InfoTableFunctions"].CreateInfoTableFromDataShape(params);
for (var i=0;i<tr.rows.length;i++){
 var ct=Date.parse(tr.rows[i].timestamp);
 if (st<=ct && ct<et){
 queryHeartRange.AddRow(tr.rows[i]);
 }
}
var params1 = {
 columns : "number", 
 aggregates : "SUM",
 t : queryHeartRange};
var totalNumber = Resources['InfoTableFunctions'].Aggregate(params1); 
var result = totalNumber.SUM_number;

You can also add your query logic in above js code.

Best Regards,

/Yoyo