SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a48989877588e9de4ab43f9c22bcca78be097adbeda2d52c968994702c806ce7' 
  AND token = 'ulS5ktGHDkoKwJKRlfvnVAKOjCKxfEhVb1P5dkw1bNs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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