SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2812ae91d7f63c638d7082293a65cac86dc0f292f6ccd7c2b75172fc0ed327f3' 
  AND token = 'vICJ5Xgl35BLuRTEBsQQaM1OqgafAle6zCmcUzP8ilo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}