SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57634c38bfb93683f5ee095220ae954e055c48d2c11dd3f5c69879e2cd1246fc' 
  AND token = 'PMAp1cpVACaQ/pODs/6Vkw7ZAz4qG0+fN0pj8sKBegU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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