<input type="text" name="artist[]" value="abc" />
<input type="text" name="artist[]" value="def" />
<input type="text" name="artist[]" value="ghi" />
<input type="text" name="artist[]" value="jkl" />
print_r($_POST);
/* array(
artist => array(
0 => "abc",
1 => "def",
2 => "ghi",
3 => "jkl"
)
) */
insert two kinds of array in the same table