SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ee1837bd1edd69221138a8f89d7823e5d5183476fcf4c9dac930f3cc2bc6487' 
  AND token = 'B0NNS44Orlr2dbo5kzDrqSXMLNlDS7deephJfSV9dTk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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