Order by date doesn't work?

[gelcaas]

When I use orderBy "date", which is defined as date "Y-m-d H:i:s" , it doesn't work, anyone can help?

Optlog::type('opt')->select('date')->search($search)->orderBy("date","desc")->paginate(10)->toArray();

result:
array:12 [
"current_page" => 1
"data" => array:10 [
0 => array:5 [
"date" => "2018-04-08 09:25:59"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKi3C_F0xeSFZ9_RGC4"
"_score" => null
]
1 => array:5 [
"date" => "2018-04-08 09:59:24"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKi-sAx0xeSFZ9_RGC8"
"_score" => null
]
2 => array:5 [
"date" => "2018-04-08 10:14:59"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKjCQNn0xeSFZ9_RGDE"
"_score" => null
]
3 => array:5 [
"date" => "2018-04-08 09:48:59"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKi8TOf0xeSFZ9_RGC6"
"_score" => null
]
4 => array:5 [
"date" => "2018-04-08 09:55:19"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKi9wAL0xeSFZ9_RGC7"
"_score" => null
]
5 => array:5 [
"date" => "2018-04-04 18:51:35"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKQSIa10xeSFZ9_RGC2"
"_score" => null
]
6 => array:5 [
"date" => "2018-04-04 18:51:09"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKQSCCz0xeSFZ9_RGC1"
"_score" => null
]
7 => array:5 [
"date" => "2018-04-08 10:14:50"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKjCOAM0xeSFZ9_RGDD"
"_score" => null
]
8 => array:5 [
"date" => "2018-04-04 18:50:43"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKQR72R0xeSFZ9_RGC0"
"_score" => null
]
9 => array:5 [
"date" => "2018-04-08 13:47:45"
"_index" => "optlog"
"_type" => "opt"
"_id" => "AWKjy83J0xeSFZ9_RGDL"
"_score" => null
]
]
"first_page_url" => "http://newadmin.ys7.com/common/searchOpt?search=&page=1"
"from" => 1
"last_page" => 2
"last_page_url" => "http://newadmin.ys7.com/common/searchOpt?search=&page=2"
"next_page_url" => "http://newadmin.ys7.com/common/searchOpt?search=&page=2"
"path" => "http://newadmin.ys7.com/common/searchOpt"
"per_page" => 10
"prev_page_url" => null
"to" => 10
"total" => 18
]