SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef4de3f4d79d7441013ee5103c8cf15a4221892132d3552f2cdbba1ccdc8f4b1' 
  AND token = 'GeqWOjBiXdRTT74470nnrR8TI6JrnromjBQBZTs1SPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}