# vi /etc/aliases

root: youremail@email.com

# newaliases

ALTER table tablename DROP FOREIGN KEY foreign_key_name

MySQL was throwing errors.

mysql> ALTER TABLE reviews DROP FOREIGN KEY priority_id;
ERROR 1025 (HY000): Error on rename of ‘./dbname/reviews’ to ‘./dbname/#sql2-62f5-145b’ (errno: 152)

If you run

SHOW CREATE TABLE tablename

You’ll see the constraint names. You can then delete the foreign key based on the constraint.

ALTER TABLE tablename DROP FOREIGN KEY `reviews_ibfk_24`;

You can then drop the column as needed.

CREATE TABLE shifts (
        id INT AUTO_INCREMENT NOT NULL,
        shift VARCHAR(15) NOT NULL,
        PRIMARY KEY(id)
) ENGINE=InnoDB;

The existing employees table needed a new column called “shift_id” that would reference the shifts table. The following code can be used to add the column and then add the foreign key constraint.

ALTER TABLE employees ADD shift_id INT AFTER group_id;
ALTER TABLE employees ADD CONSTRAINT FOREIGN KEY(shift_id) REFERENCES shifts(id) ON UPDATE CASCADE ON DELETE SET NULL;

The first alter statement worked fine, but the second kept throwing an error 150. You can view more details about the last error with the following:

SHOW INNODB STATUS;

I would see the following:

————————
LATEST FOREIGN KEY ERROR
————————
110805 8:49:16 Error in foreign key constraint of table backlogreviews/#sql-62f5_23:
FOREIGN KEY(shift_id) REFERENCES shifts(id) ON UPDATE CASCADE ON DELETE SET NULL:
Cannot resolve table name close to:
(id) ON UPDATE CASCADE ON DELETE SET NULL

This didn’t exactly help as I know the shifts table exists. I did some searching on google and found some hints, but these mostly indicated the column doesn’t match up correctly. Turns out I had a syntax error when creating the shifts table. The engine was INNOBD (notice the BD should read DB). Instead of throwing an error when creating the table it just used MyISAM. Since the storage engines didn’t match I was getting the error.

mysql> grant all privileges on *.* to root@'remote_machone' identified by 'root password';
Query OK, 0 rows affected (0.12 sec)

You may not want to use the root account, but this will give you remote access.

Validation should always happen in the model so I created a new function that would check for the current password for the logged in user. The Auth component automatically hashes the password with SHA1 and uses the Security Salt as part of the password string to create the hash, so I needed to hash the “current_password” field from the form to check for a match. This is where I ran into the problem. I tried using the following:

function checkCurrentPassword($data) {
    $id = $this->data[$this->alias]['id']; // passed the user ID from the form as a hidden field
    $pwd = $this->field('password', array('id' => $id)); // get the current password from the database
    if(Security::hash($data['current_password']) != $pwd) {
        return false;
    }
    return true;
}

You can see that $id is passed from the form and $pwd is a variable for the current password in the database. Auth will automatically hash an input with the name “password”, but my form is using “current_password”, so it is sent in cleartext. This needs to be hashed first. I attempted to use the Security::hash function but my validated kept failing.

As it turns out the Security::hash function is only using SHA1 without the Security Salt added. What I was able to do is use the AuthComponent::password function instead which does use the Security Salt configured in core.php. New code looks like:

function checkCurrentPassword($data) {
    $id = $this->data[$this->alias]['id'];
    $pwd = $this->field('password', array('id' => $id));
    if(AuthComponent::password($data['current_password']) != $pwd) {
        return false;
    }
    return true;
}

The validate array would look like this:

var $validate = array(
'current_password' => array(
    'rule' => 'checkCurrentPassword',
    'message' => 'Current password was not entered correctly'
    )
);

Update: Security::hash actually takes a third parameter documented in the API to use the Security.salt value

Create a hash from string using given method. Fallback on next available method.

Parameters:

string $string required

String to hash
string $type optional NULL

Method to use (sha1/sha256/md5)
boolean $salt optional false

If true, automatically appends the application’s salt value to $string (Security.salt)

I recently had to build a list on distinct dates, but prefer to user $this->Form->input, rather than $this->Form->select. I first built an indexed array containing my date fields.

array(
[xxxx-xx-xx] => xxxx-xx-xx
[yyyy-yy-yy] => yyyy-yy-yy
)

We’ll call this array $options. You can then build the input using something like

$this->form->input('Input Name', array(
  'type' => 'select',
  'options' => 'options',
  'label' => 'label',
  'empty' => 'No data selected'
);

My example uses an Employee model.

class Employee extends AppModel {
	var $name = 'Employee';
        var $virtualFields = array('full_name' => 'CONCAT(Employee.firstname, " ", Employee.lastname)');
        var $displayField = 'full_name';
}

Target file system doesn’t have /sbin/init
No init found. Try passing init= bootarg

Busybox v1.13.3 (Ubuntu 1:1.13.3-1ubuntu7) built-in shell (ash)
Enter ‘help’ for a list of built-in commands
(initramfs) _

Not very happy about this. Running “help” didn’t reveal any tools that would repair the boot volume. To recover I booted to an Ubuntu 10.10 CD and select the option to “Try Ubuntu”. Once this started I used Ctrl + Alt + F1 to get to a shell and ran the following:

sudo fdisk -l
sudo fsck /dev/sda1

Running fdisk -l was just to be sure of the naming convention for my main drive, which in this case was /dev/sda1. I had to enter yes a couple times and then rebooted the machine which loaded successfully.

mkdir /usr/src/pure-ftpd
cd /usr/src/pure-ftpd

apt-get source pure-ftpd
apt-get build-dep pure-ftpd

Edit the rules file and add the following to optflags [--without-capabilities]

cd pure-ftpd-1.0.21/debian
vi rules

optflags=–with-everything –with-largefile –with-pam –with-privsep –with-tls –without-capabilities

Build the package and install it.

cd ..
dpkg-buildpackage -uc -b

cd ..
dpkg -i pure-ftpd-common_1.0.21-11.4_all.deb pure-ftpd-mysql_1.0.21-11.4_i386.deb
/etc/init.d/pure-ftpd-mysql restart

Prevent the package manager from trying to update pure-ftpd

echo 'pure-ftpd-common hold' | dpkg --set-selections
echo 'pure-ftpd-mysql hold' | dpkg --set-selections