SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '600066cab4600168c6f87b9c2a1a3db1e8b6474a99acb15a20c1af52a070fedb' 
  AND token = 'tLajqEwGHCtoKqNtibG5/RYTPmADu+i5wDbSiliv9D0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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