SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc48529ed9e746491966821a323d5aa9905dadba03b579d78d2d4f4548f9279b' 
  AND token = 'uTnf+z1s2Uc0F4fJLtqTnWn9ujNv5cO7W7KQ9lGZeFM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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