SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26f5bffa055874f7145a4b9535c6b3150adf6873c81b750a7465d5c32c101210' 
  AND token = 'HGi/GiXuX2lkFmdJRUnRoLOV+BCgSvDEJFvxVruK3Uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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