SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09127d629522d42cca6367c12b1435ef45f92cb429905df1e7db7b3c01d4a8c5' 
  AND token = '6wyNMhs8bvyhGYQSsEvFdHZ+h3NIALtoifANqMISb6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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