The string below actually represents an array in serialized form.
a:1:{s:13:"administrator";s:1:"1";}
Here:
a:1 means an array with a single element
s:13 means string and the length of the string followed by
Array
{
"administrator" => "1"
}
Once that is in the table, you can use the unserialize() function to return it to an array for use in your code.
Many thanks.