SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0d925fd6cb47a067b271b4ecb9e029956e21943f88e677038afa3448424dd88' 
  AND token = 'JXVhhhGcMxbCfw0TjgwtE8vWm8D+LpljpXioZKTAZds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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