SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a744eb7130567bf8f6601acca5a905695078f528e13163a2ffd28b50b506e75' 
  AND token = 'd0RPCDXwuMMcqPQ7rsIUQ3Ukcjfb0iIHHeAD7bCwgAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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