A Framework for Persisting Data Relationships

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July 12th, 2003, 05:01 PM

jmc

Join Date: Apr 2007

Posts: 9

Time spent in forums: < 1 sec
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A Framework for Persisting Data Relationships

Can anyone help me modify Jakes script from the article.

I have changed what I think is necessary to make it work, the form works and tells me to check the database but no records are added.

My database contains the following tables etc.

cd_artists
==========
Artist_ID
CompactDisc_Artist

cd_compactdiscs
===============
CompactDisc_ID
CompactDisc_Title

cd_artist2cd
============
Artist_ID
CompactDisc_ID

I think the problem is to do with the arrays.

php Code:

Original - php Code

<?php
//cd.php
if (isset($_POST['submit'])) {
echo "submitting <br>";
include_once("cd_classes.php");

// new Compactdisc:; 
$newCompactdisc = new Compactdisc;
$newCompactdisc->title = ($_POST['title']);
$newCompactdisc->PersistNew();

// new Artist
$newArtist = new Artist;
$newArtist ->artistname = ($_POST['artist']);
$newArtist->PersistNew();

// new Link
$newCompactdiscArtistLink = new CompactdiscArtistLink;
$newCompactdiscArtistLink ->artist = $newArtist->id;
$newCompactdiscArtistLink ->cd = $newCompactdisc->id;
$newCompactdiscArtistLink->PersistNew();

echo "done, check out the database";
} else {
?>
<html>
<form method="POST" action="cd.php">
<table>
  <tr>
    <td>Compact Disc Title:</td>
    <td><input name="title" /></td>
  </tr>
  <tr>
    <td>Compact Disc Artist:</td>
    <td><input name="artist" /></td>
  </tr>
  <tr>
    <td><input type="submit" name="submit" value="submit" /></td>
    <td><input type="reset" /></td>
  </tr>
</table>
</form>
</html>
<?php
}
?>
=======

<?php
// cd_classes.php

// A database persitable object, pretty useless unless you extend it.   
class Persistable {

// Unique database identifier.
      var $id; 
      // Table name that is used in the database
      var $table; 
      // Map of column labels in the database to object variables
      var $columns = array();

// Persist a new object in the database. 
      function PersistNew() { 
        mysql_connect('localhost', 'xxx', 'xxx')
                  or die("Could not connect: " . mysql_error());
        mysql_select_db('jamesmcl_cms') 
              or die ("Unable to select database");
        
        $sql = "INSERT INTO `".$this->table."` ";
        $labels = "(`id` ";
        $values = ") VALUES ('' ";

foreach ($this->columns as $column) {
          $labels .= ", `".$column[0]."` ";
          $temp = '$this->'.$column[1];
          $values .= ", '"."$temp"."' ";    
          unset($temp);
        }

$sql .= $labels.$values.")";
        eval ("$sql = "$sql";");
        $result = mysql_query($sql);
        $this->id = mysql_insert_id();
      }
}// End Class Persistable

class Book extends Persistable {

var $title;//String of book title.

function Book() { //Constructor for Book.
        $this->table = 'test_books';
        $this->columns = array( array('title','title')
                              );
      }
} // End Class Book

class Author extends Persistable {
   
      var $fname; // String of author first name.  
      var $lname; // String of author last name.
    
      function Author() { //Constructor for Author.
        $this->table = 'test_authors';
        $this->columns = array( array('firstname','fname'),
                                array('lastname','lname')
                              );
      }
} // End Class Author

class BookAuthorLink extends Persistable {
   
      var $book; // integer book unique id.  
      var $author; //  integer author unique id.
    
      function BookAuthorLink() { //Constructor for Author.
        $this->table = 'test_bookauthorlink';
        $this->columns = array( array('book','book'),
                                array('author','author')
                              );
      }
} // End Class BookAuthorLink

class Compactdisc extends Persistable {

var $title;//String of book title.

function Compactdisc() { //Constructor for Compactdisc.
        $this->table = 'cd_compactdiscs';
        $this->columns = array( array('CompactDisc_Title','title')
                              );
      }
} // End Class Compactdisc

class Artist extends Persistable {
   
      var $artistname; // String of artist name.  
      
    
      function Artist() { //Constructor for Artist.
        $this->table = 'cd_artists';
        $this->columns = array( array('CompactDisc_Artist','artistname')
                               );
      }
} // End Class Artist

class CompactdiscArtistLink extends Persistable {
   
      var $cd; // integer cd unique id.  
      var $artist; //  integer artist unique id.
    
      function CompactdiscArtistLink() { //Constructor for CompactdiscArtist.
        $this->table = 'cd_artist2cd';
        $this->columns = array( array('cd','cd'),
                                array('artist','artist')
                              );
      }
} // End Class CompactdiscArtistLink
?>

 
<?php
//cd.php
if (isset($_POST['submit'])) {
echo "submitting <br>";
include_once("cd_classes.php");
 
// new Compactdisc:; 
$newCompactdisc = new Compactdisc;
$newCompactdisc->title = ($_POST['title']);
$newCompactdisc->PersistNew();
 
// new Artist
$newArtist = new Artist;
$newArtist ->artistname = ($_POST['artist']);
$newArtist->PersistNew();
 
// new Link
$newCompactdiscArtistLink = new CompactdiscArtistLink;
$newCompactdiscArtistLink ->artist = $newArtist->id;
$newCompactdiscArtistLink ->cd = $newCompactdisc->id;
$newCompactdiscArtistLink->PersistNew();
 
echo "done, check out the database";
} else {
?>
<html>
<form method="POST" action="cd.php">
<table>
  <tr>
    <td>Compact Disc Title:</td>
    <td><input name="title" /></td>
  </tr>
  <tr>
    <td>Compact Disc Artist:</td>
    <td><input name="artist" /></td>
  </tr>
  <tr>
    <td><input type="submit" name="submit" value="submit" /></td>
    <td><input type="reset" /></td>
  </tr>
</table>
</form>
</html>
<?php
}
?>
=======
 
<?php
// cd_classes.php
 
// A database persitable object, pretty useless unless you extend it.   
class Persistable {
 
      // Unique database identifier.
      var $id; 
      // Table name that is used in the database
      var $table; 
      // Map of column labels in the database to object variables
      var $columns = array(); 
 
      // Persist a new object in the database. 
      function PersistNew() { 
        mysql_connect('localhost', 'xxx', 'xxx')
                  or die("Could not connect: " . mysql_error());
        mysql_select_db('jamesmcl_cms') 
              or die ("Unable to select database");
        
        $sql = "INSERT INTO `".$this->table."` ";
        $labels = "(`id` ";
        $values = ") VALUES ('' ";
 
        foreach ($this->columns as $column) {
          $labels .= ", `".$column[0]."` ";
          $temp = '$this->'.$column[1];
          $values .= ", '"."$temp"."' ";    
          unset($temp);
        }
 
        $sql .= $labels.$values.")";
        eval ("$sql = "$sql";");
        $result = mysql_query($sql);
        $this->id = mysql_insert_id();
      }
}// End Class Persistable
 
class Book extends Persistable {
 
      var $title;//String of book title.
 
      function Book() { //Constructor for Book.
        $this->table = 'test_books';
        $this->columns = array( array('title','title')
                              );
      }
} // End Class Book 
 
class Author extends Persistable {
   
      var $fname; // String of author first name.  
      var $lname; // String of author last name.
    
      function Author() { //Constructor for Author.
        $this->table = 'test_authors';
        $this->columns = array( array('firstname','fname'),
                                array('lastname','lname')
                              );
      }
} // End Class Author
 
class BookAuthorLink extends Persistable {
   
      var $book; // integer book unique id.  
      var $author; //  integer author unique id.
    
      function BookAuthorLink() { //Constructor for Author.
        $this->table = 'test_bookauthorlink';
        $this->columns = array( array('book','book'),
                                array('author','author')
                              );
      }
} // End Class BookAuthorLink
 
class Compactdisc extends Persistable {
 
      var $title;//String of book title.
 
      function Compactdisc() { //Constructor for Compactdisc.
        $this->table = 'cd_compactdiscs';
        $this->columns = array( array('CompactDisc_Title','title')
                              );
      }
} // End Class Compactdisc 
 
class Artist extends Persistable {
   
      var $artistname; // String of artist name.  
      
    
      function Artist() { //Constructor for Artist.
        $this->table = 'cd_artists';
        $this->columns = array( array('CompactDisc_Artist','artistname')
                               );
      }
} // End Class Artist
 
class CompactdiscArtistLink extends Persistable {
   
      var $cd; // integer cd unique id.  
      var $artist; //  integer artist unique id.
    
      function CompactdiscArtistLink() { //Constructor for CompactdiscArtist.
        $this->table = 'cd_artist2cd';
        $this->columns = array( array('cd','cd'),
                                array('artist','artist')
                              );
      }
} // End Class CompactdiscArtistLink
?>

July 14th, 2003, 05:18 AM

drevele

Join Date: Apr 2007

Location: Medina, Ohio

Posts: 233

Time spent in forums: < 1 sec
Reputation Power: 2

RE: A Framework for Persisting Data Relationships

Im not the smartest at arrays but array(array(
dosent seem right.
Why not just use: array('bla', 'bla');
Instead of having:
$my_array = array(array('Test1,'Test2'););
Array -
1. array-
1. Test1
2. Test2
Why not have
$my_array = array('Test1', 'Test2');
Array-
1. Test1
2. Test2

It is alot simpler

July 14th, 2003, 05:49 PM

jmc

Join Date: Apr 2007

Posts: 9

Time spent in forums: < 1 sec
Reputation Power: 0

RE: A Framework for Persisting Data Relationships

drevele,
the original code with the arrays works fine.

I have tried to change it to work with my cd tables and I cant see where I'm going wrong. I presume that its to do with the variables and database fields.

In the example

php Code:

Original - php Code
class Author extends Persistable { var $fname; // String of author first name. var $lname; // String of author last name. function Author() { //Constructor for Author. $this->table = 'test_authors'; $this->columns = array( array('firstname','fname'), array('lastname','lname') ); } } // End Class Author

 
class Author extends Persistable {
   
      var $fname; // String of author first name.  
      var $lname; // String of author last name.
    
      function Author() { //Constructor for Author.
        $this->table = 'test_authors';
        $this->columns = array( array('firstname','fname'),
                                array('lastname','lname')
                              );
      }
} // End Class Author

firstname and lastname are database fields

Any ideas

July 14th, 2003, 10:40 PM

drevele

Join Date: Apr 2007

Location: Medina, Ohio

Posts: 233

Time spent in forums: < 1 sec
Reputation Power: 2

RE: A Framework for Persisting Data Relationships

php Code:

Original - php Code

      function PersistNew() {
        mysql_connect('localhost', 'xxx', 'xxx')
                  or die("Could not connect: " . mysql_error());
        mysql_select_db('jamesmcl_cms')
              or die ("Unable to select database");
        
        $sql = "INSERT INTO `".$this->table."` ";
        $labels = "(`id` ";
        $values = ") VALUES ('' ";
 
        foreach ($this->columns as $column) {
          $labels .= ", `".$column[0]."` ";
          $temp = '$this->'.$column[1];
          $values .= ", '"."$temp"."' ";    
          unset($temp);
        }

When is $this->table defined?