Automatically E-mail MySQL Database Backup

If you are in a hosting environment where you are responsible for your own database backups, this is a convenient way to have the server generate a backup file of all of your MySQL databases, compress the file, and e-mail it to the specified address. I’ve added this to the local crontab so that it runs on a regular schedule. In order for it to work, you should have a MySQL user account created with the appropriate privileges in order to access your database.

In the crontab, create an entry, as follows, with your customization for both the path to your configuration file and the e-mail address receiving the backup.

mysqldump --defaults-extra-file="/path/to/config/file/.mysqldump.cnf"
          --all-databases
          -ce
  | gzip
  | uuencode dbbackup.gz
  | /usr/sbin/sendmail my_e-mail_address

In the .mysqldump.cnf file, provide the username and associated password that can access the database. Secure .mysqldump.cnf by setting the file permissions 0600 since that file contains your database password in plaintext.

[client]
user=my_database_username
password=my_database_user_password

Select a Drop-down List Item Using JavaScript

The following JavaScript functions are useful for selecting items in HTML drop-down lists. As an example, these can be used if you have server-side code returning values that should then be visually selected on the user’s screen without rebuilding the entire page.

<select id="country_list" name="country_list">
  <option value="1">USA</option>
  <option value="2">Canada</option>
  <option value="3">Mexico</option>
</select>

This first function selects an item based on its value. Pass an object referring to a list element, e.g., document.getElementById(“country_list”), and the value that should be selected.

function selectItemValue(list, selectedValue) {
  for(j = 0; j < list.options.length; j++) {
    if(toUpper(list.options[j].value) == toUpper(selectedValue)) {
      list.selectedIndex = j;
      break ;
    }
  }
}

This second function will select an item based on its displayed text name. Pass in an object referring to a list element, e.g., document.getElementById(“country_list”), and the displayed text value that should be selected.

function selectItemText(list, selectedText) {
  for(j = 0; j < list.options.length; j++) {
    if(toUpper(list.options[j].text) == toUpper(selectedText)) {
      list.selectedIndex = j;
      break ;
    }
  }
}

The following is an example of how to call both functions using the example list:

selectItemValue(document.getElementById("country_list"), 1);
selectItemText(document.getElementById("country_list"), "USA");

Disable All Links Within DIV

This JavaScript function disables all links within the specified DIV by setting the link object to ‘disabled’ as well as removing the ‘onclick’ and ‘href’ attributes. This is a useful JavaScript function for form submissions since it prevents the user from clicking another link while an action is pending.

function DisableAllDIVLinks(DivId) {
  var div = document.getElementById(DivId);
  var anchorList = div.getElementsByTagName('a');

  for(var i = 0; i < anchorList.length; i++) {
    anchorList[i].disabled = true;
    anchorList[i].onclick = '';
    anchorList[i].removeAttribute('href');
  }
}

The following is a modified version that disables all links within a specified DIV, but it retains a backup of the links so that they can be re-enabled with the EnableAllDIVLinks function.

function DisableAllDIVLinks(DivId) {
  var div = document.getElementById(DivId);
  var anchorList = div.getElementsByTagName('a');

  for(var i = 0; i < anchorList.length; i++) {
    anchorList[i].disabled = true;
    anchorList[i].setAttribute('backup_href', anchorList[i].getAttribute("href"));
    anchorList[i].removeAttribute('href');
  }
}

function EnableAllDIVLinks(DivId) {
  var div = document.getElementById(DivId);
  var anchorList = div.getElementsByTagName('a');

  for(var i = 0; i < anchorList.length; i++) {
    anchorList[i].disabled = false;
    anchorList[i].setAttribute('href', anchorList[i].getAttribute("backup_href"));
    anchorList[i].removeAttribute('backup_href');
  }
}