遍历数组，利用数组内的值查询数据库数据，将数据库查询出来的值重新组成一个数组。
foreach循环拿出来想要的单个值，在循环里面查询数据，
需要遍历的数组：
array(7) { [0]=> array(1) { [“user_id”]=> string(1) “9” } [1]=> array(1) { [“user_id”]=> string(2) “10” } [2]=> array(1) { [“user_id”]=> string(2) “11” } [3]=> array(1) { [“user_id”]=> string(2) “28” } [4]=> array(1) { [“user_id”]=> string(2) “42” } [5]=> array(1) { [“user_id”]=> string(2) “45” } [6]=> array(1) { [“user_id”]=> string(2) “55” } } 利用‘9’，10，查询数据库
查询语句：
string
(130) "SELECT user_id, user_name, last_time FROM `newoa`.`xdd_users` WHERE shop_status = 5 AND last_time < 1600557299 AND operater_id = 9"
数据：
array
(7) {
[0]=> array
(3) {
["user_id"]=> string
(1) "1" ["user_name"]=> string
(6) "响丁当" ["last_time"]=> string
(10) "1574708053" }
[1]=> array
(3) {
["user_id"]=> string
(3) "311" ["user_name"]=> string
(10) "shiauthing" ["last_time"]=> string
(10) "1582067358" }
[2]=> array
(3) {
["user_id"]=> string
(3) "332" ["user_name"]=> string
(4) "孙健" ["last_time"]=> string
(10) "1562003534" }
[3]=> array
(3) {
["user_id"]=> string
(3) "414" ["user_name"]=> string
(6) "周莎莎" ["last_time"]=> string
(10) "1596303254" }
[4]=> array
(3) {
["user_id"]=> string
(3) "643" ["user_name"]=> string
(6) "投资部" ["last_time"]=> string
(1) "0" }
[5]=> array
(3) {
["user_id"]=> string
(3) "695" ["user_name"]=> string
(4) "范磊" ["last_time"]=> string
(1) "0" }
[6]=> array
(3) {
["user_id"]=> string
(3) "712" ["user_name"]=> string
(6) "田正芳" ["last_time"]=> string
(1) "0" } }
$sql_peo = "SELECT role_id FROM " .$ecs->table('admin_user')."WHERE user_id =".$_SESSION['admin_id'];
$sql_peo_value = $db->getAll($sql_peo);
$sql_peo_0 = "SELECT user_id FROM " .$ecs->table('admin_user')."WHERE role_id =".$sql_peo_value[0]["role_id"];
$sql_peo_0_value = $db->getAll($sql_peo_0);
$a = array();
foreach ($sql_peo_0_value AS $key => $value)
{
$sql = "SELECT user_id, user_name, last_time FROM ".$ecs->table('users')." WHERE shop_status = 5 AND last_time < ".(gmtime()-2592000)." AND operater_id = ". $sql_peo_0_value[$key]['user_id'];
$comentlist = $db->getAll($sql);
$a = $a + $comentlist;
}
$comentlist = $a;
解决办法：
先把二维数组转成一维数组，然后 select from where id in 那个数组
