// Create dummy infotables to merge (no datashapes necessary here)
var table1 = Resources["InfoTableFunctions"].CreateInfoTable({infoTableName: "Table1"});
table1.AddField({name:"StringField1",baseType:"STRING"});
table1.AddField({name:"DateTimeField",baseType:"DATETIME"});
var newEntry1 = new Object();
newEntry1.StringField1 = "test value";
newEntry1.DateTimeField = Date.now();
table1.AddRow(newEntry1);

var table2 = Resources["InfoTableFunctions"].CreateInfoTable({infoTableName: "Table2"});
table2.AddField({name:"StringField2",baseType:"STRING"});
table2.AddField({name:"DateTimeField",baseType:"DATETIME"});
var newEntry2 = new Object();
newEntry2.StringField2 = "other test value";
newEntry2.DateTimeField = Date.now();
table2.AddRow(newEntry2);



var table3 = Resources["InfoTableFunctions"].CreateInfoTable({infoTableName: "Table3"});
table3.AddField({name:"StringField3",baseType:"STRING"});
table3.AddField({name:"DateTimeField",baseType:"DATETIME"});
var newEntry3 = new Object();
newEntry3.StringField3 = "other test value";
newEntry3.DateTimeField = Date.now();
table3.AddRow(newEntry3);

// Create the results table
var combined_infotable = Resources["InfoTableFunctions"].CreateInfoTable({infoTableName: "ResultsTable"});

// Create list of tables to merge (can do more than two)
var tableList = [table1, table2, table3];

// Iterate through the fields of each table, adding the fields to the results table if necessary and then setting the values
for(var i = 0; i < tableList.length; i++) {
    var currentTable = tableList[i];
     // Need to convert to json in order to iterate through fields if datashape is not known. If datashape is known, see snippets for potentially simpler solution
    var table_json = Resources["InfoTableFunctions"].ToJSON({table: currentTable});

    for(var key in table_json.dataShape.fieldDefinitions) {
        try { // this line will error if the field doesn't already exist in the results table...
            combined_infotable.dataShape.fieldDefinitions[key]
        } catch(err) { // ...so if it does error, then we need to add it
            combined_infotable.AddField(table_json.dataShape.fieldDefinitions[key]);
        }
    }

    // Now iterate through the values of each table and copy over each row
    for(var j = 0; j < currentTable.rows.length; j++) {
        combined_infotable.AddRow(currentTable.rows[j]);
    }
}

var result = combined_infotable;