Deleting data from Drive Tables and automatically re-importing new data - google-app-maker

Question

I need help with trying to understand how to delete all data from a table and then try to automatically import a new sheet with data into the newly cleared down table.
I'm currently trying the unload() method client side but that doesn't seem to cleardown my tables
function ClearDown(){
app.datasources.P11d.unload(function(){});
console.log('Finish Delete');
}
I've also tried to create a server side function, which also doesn't appear to work
function ClearTable(){
var records = app.models.P11d.newQuery();
// records.run();
console.log('Server Function Ran');
app.deleteRecords(records.run());
}
This is ran from a client side function:
function Delete(){
google.script.run.withSuccessHandler(function(result){
}).ClearTable();
console.log('Function Ran');
}
Again this is all to no avail
With the import side I've tried to do the below:-
Client Side:
function ImportData(){
console.log('Begin');
var ss = SpreadsheetApp.openById('SHEET ID');
var values = ss.getSheetByName('P11d').getDataRange().getValues();
var ssData = [];
// app.datasources.P11d.unload(function(){});
for (var i = 0; i<values.length; i++){
var newRecord = app.models.P11d.newRecord();
// add all fields to the new record
newRecord.Reg_Number = values[i][0];
newRecord.Reg_Date = values[i][1];
newRecord.Model_Description = values[i][2];
newRecord.P11d_Value = values[i][3];
newRecord.EngineSize = values[i][4];
newRecord.Fuel = values[i][5];
newRecord.CO2 = values[i][6];
newRecord.SIPP = values[i][7];
newRecord.GTA_Code = values[i][8];
newRecord.Type = values[i][9];
ssData.push(newRecord);
// console.log(newRecord.MODEL_FIELD);
}
console.log('Finished');
// return the array of the model.newRecord objects that would be consumed by the Model query.
}
Please can someone help with this, at the moment the way the data is sent over to me adding new stuff into the Drive Table is causing many duplicates.
Thanks in advance,

Answer 1

You can delete all records, import, and read from a spreadsheet using the AMU Library
Copy and paste the server and client scripts into your app.
I'm sure that will make it much easier!
To delete all the data in a model using this:
Button onClick:
google.script.run.AMU.deleteAllData('ModelName');
The correct way to delete records on the server is:
app.models.MODEL_NAME.deleteRecords(key_array);
datasource.unload() simply unloads the widget on the client. It does not affect the database records.
A better way to write your records query on the server is:
var query = app.models.MODEL_NAME.newQuery();
query.filters.your_filter_here;
var records = query.run();
Note that you cannot return a single record or an array of records from anything but a calculated model function without using a function posted here. (You can return a single field of a record using stringify for any json data.)
I am currently working on a solution to create datasource independent tables needed in App Maker.

Answer 2

For the delete function on the server try to change your code just a little bit, this function at least used to work for me, however I have not needed to use it in some time.
function ClearTable(){
var records = app.models.P11d.newQuery().run();
console.log('Server Function Ran');
app.deleteRecords(records);
}