<?php
$arr = array ('a'=>1,'b'=>2,'c'=>3,'d'=>4,'e'=>5);
// of course this array can be created by looping through your mysql result set
// and doing a mysql_fetch_assoc
// for example, $sql = your query here
// mysql_fetch_assoc($result); etc
echo json_encode($arr);
?>
{"a":1,"b":2,"c":3,"d":4,"e":5}
Тогда вы можете сделать что-то вроде
<script type="text/javsacript">
var abc = "<? echo json_encode($arr);?>";
</script>
OR
echo '<script type="text/javsacript">
var abc ="'.json_encode($arr).'";
</script>';