SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73999c94d3b238c486b6cbb3e2cd61a95be7ae60260ff6816896d05c20eb2735' 
  AND token = 'wfLzML5rSsV1pBxtIvCz/JzolauSZ3ddVrH1FuaQRjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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