Render_sql question (using with DataView)

Suite and Optimus Suite 5
#1

I have 2 tables,
tableA (mySQL DB columns: idx,valueX, valueY)
tableB (mySQL DB columns: id, idx,valueZ)

tableA
idx | valueX | valueY
1 | x1 | y1
2 | x2 | y2
3 | x3 | y3
4 | x4 | y4
5 | x5 | y5

tableB
id | idx | valueZ
1 | 3 | z3
2 | 4 | z4

I am using render_sql to show data in DHTMLX Dataview and code below works OK.

$t1=tableA;
$t2=tableB;
$data->render_sql("Select * from $t1 LEFT JOIN $t2 ON $t1.idx = $t2.idx","","valueX,valueY,valueZ");

However, i want to display the “idx” value as well to Dataview. But i am unable to do so!!
For example: i have tried all options below but they dont seem to work

$data->render_sql("Select * from $t1 LEFT JOIN $t2 ON $t1.idx = $t2.idx","","$t1.idx,valueX,valueY,valueZ");
$data->render_sql("Select * from $t1 LEFT JOIN $t2 ON $t1.idx = $t2.idx","","tableA.idx,valueX,valueY,valueZ");

Am i missing something?

#2

Because the name of field is the same in the both tables , you need to assign unique alias to that field

$data->render_sql("Select *, $t1.idx as showID from $t1 LEFT JOIN $t2 ON $t1.idx = $t2.idx","","showID,valueX,valueY,valueZ");

or

$data->render_sql("Select * from $t1 LEFT JOIN $t2 ON $t1.idx = $t2.idx","","idx($t1.idx),valueX,valueY,valueZ");