SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db9845f9e1c9868f1397ace1c222aa1b86311d1e3ef86f83b48580e4c4444e7c' 
  AND token = 'aJP1lQhaKFTbPVCPkXgTtclzrS/W/lSBUvHuJqKajrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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