How to insert sign date "now()" in database ?????

Question

I am a newbie.  Using DW CS5 I have been able to get a number of web pages on my web site to work well.  My problem is with my “sign in form”.  I want to add in the sign in form a hidden field for the date that the user signs up.
But the signup_date value in the database is not been entered.  I do have a “work around”.  If I replace the last “%s” in the $insertSQL statement with NOW(), the correct signup_date is entered in the database table “users”.  However, I want to learn to do it “right”.  My questions:
1.      What is the “best” way to accomplish my desire results?
2.      What do the “%s” stand for in the $insertSQL statement?  I think it is an array, but I do not understand this line of code that DW generated.  Can you explain is plain English?
Below is the important part of the code (I hope I sent enough to explain the problem) for the sign form: (disregard the /////// they are only there to indicate different sections of the code).
//This is the code from the input form for the hidden field "signup_date"
</tr>
    <tr>
      <td align="left" valign="top"><input name="signup_date" type="hidden" id="signup_date" value="NOW()" />
      <td><input type="submit" name="Submit" value="Join Now!"></td>
    </tr>
  </table>
//This is the dreamweaver code to insert the date into the data base:
if ((isset($_POST["MM_insert"])) && ($_POST["MM_insert"] == "frJoin")) {
  $insertSQL = sprintf("INSERT INTO users (first_name, last_name, email_address, username, info, user_level, signup_date) VALUES (%s, %s, %s, %s, %s, %s, %s)",
                       GetSQLValueString($_POST['first_name'], "text"),
                       GetSQLValueString($_POST['last_name'], "text"),
                       GetSQLValueString($_POST['email_address'], "text"),
                       GetSQLValueString($_POST['username'], "text"),
                       GetSQLValueString($_POST['info'], "text"),
                       GetSQLValueString($_POST['user_level'], "text"),
                       GetSQLValueString($_POST['signup_date'], "date"));
Thanks !!

Answer 1

I do have a “work around”.  If I replace the last “%s” in the $insertSQL statement with NOW(), the correct signup_date is entered in the database table “users”.  However, I want to learn to do it “right”.
Your "workaround" is actually the correct method. The way that you think is "right", by entering the date into a hidden field, is actually the wrong way. Hidden fields can be manipulated. Inserting data directly into the query is the desired method, like the method you are currently using. It's not a "workaround", it's the correct method. You hidden field is not working because you have not told the page that the NOW() in the hidden field should be processed through php. NOW() is MySQL function. Use php to echo current date in hidden field if you want to use the "wrong" method of processing the date into your query.
<td align="left" valign="top"><input name="signup_date" type="hidden" id="signup_date" value="<?php echo date("Y-m-d H:i:s"); ?>" />