SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '56e0abb447e2354807a25b90050daf27e3c297bd84687e5f806ae987a61bdca5' 
  AND token = 'FWqOsaG/efFdIyotruHh9Wwfv7S/zFEY0igDqBpddl0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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