SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87456c13b95e77d2962a7a3565ddecf96cfe4f116516c0fe4347ecb58ccc3193' 
  AND token = 'VhtQj2MZXkK9Vq8RZUDgh5z5zTJJVB/vSYiT3SgBuoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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