SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18711ebb55a39cf6a15f642b7894ab1c2e29f9e3cc8dc68be3c8d69d72aacfd6' 
  AND token = 'V9p/Cb+42XCpJxI3F6PNqXm8ApKZ75n/hcegN8bHA64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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