SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e08476c9c3a042d65bc58cc5a097ec3adfc9374e41cc884ee27e7ec3075aa0a' 
  AND token = 'fxGVRSGpDY+k9JkVH/7OVP8VuQxMyzfspQPKanqlyw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00059

JSON explain

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