[1] : select tid from user_post where pid='628720' limit 1 

Array
(
    [tid] => 628721
)
Array
(
    [0] => http://play.nownews.com/wp-content/uploads/2019/04/1555499212-5ba04f5620c6f16272915c3a0dbbf68b.jpg
    [1] => https://www.nownews.com/wp-content/uploads/2019/04/1555498274-d8d81b6e992f3579cf3e956241192bf7.jpg
    [2] => https://www.nownews.com/wp-content/uploads/2019/04/1555498339-c824d42e51583c7f7479809f63aa95c4.jpg
    [3] => https://www.nownews.com/wp-content/uploads/2019/04/1555498592-0a4a7854f9384f4ba68afc95a50a43fd.jpg
)
[2] : stage2
[3] : stage3
[4] : http://play.nownews.com/wp-content/uploads/2019/04/1555499212-5ba04f5620c6f16272915c3a0dbbf68b.jpg
Return
(1 : 4)
[5] : https://www.nownews.com/wp-content/uploads/2019/04/1555498274-d8d81b6e992f3579cf3e956241192bf7.jpg
(2 : 4)
[6] : https://www.nownews.com/wp-content/uploads/2019/04/1555498339-c824d42e51583c7f7479809f63aa95c4.jpg
(3 : 4)
[7] : https://www.nownews.com/wp-content/uploads/2019/04/1555498592-0a4a7854f9384f4ba68afc95a50a43fd.jpg
(4 : 4)
ReturnStart Cap