SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ecd9900fb52dadb5ee39879f33828fe843ca89ecca5775e526c52d1e42d52106' 
  AND token = 'Tk+paQfKaxivbTTvu2AhQTAxe45/t6RQSjQMPjVWRM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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