[RESOLVED] duplicate record when inserting, how to prevent?

[bluemonster]

i encountered duplicate record when inserting to mysql, how do u prevent?

$query_categoryObj = "Select category_id from categoryTable where category_name='$category_name'";
$categoryObj = mysql_query($query_categoryObj) or die(mysql_error());
$totalRows= mysql_num_rows($categoryObj);
if($totalRows= 0) {
  $query="Insert into categoryTable(category_name,   category_status) Values('$category_name', '1')";
  mysql_query($query);

If user refresh the page, it will insert double.

can advise me

[abc123]

One problem I can see is that you need a double equals "==" in your if statement.

[laserlight]

You should also declare category_name to be a unique column. In fact, you can avoid a possible race condition error by just attempting the insert, and then checking the return error code for an attempted violation of the unique constraint.

[bluemonster]

can show me example, cos it inserting double entry.

[abc123]

What code do you have now?

[bluemonster]

sorry, my mistake, solved.