SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dde7ccc2ed8e2091faa8bf9d41ca0b561d46aedd8ed6a9b532a8171247069204' 
  AND token = 'B5obeL2sSjkV98JxmXC0wJ+TnE4J6Tyn6ksGvM0DyMQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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