Урок - Database Быстрый старт: Примеры кода.

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The following page contains example code showing how the database class is used. For complete details please read the individual pages describing each function.

 

Initializing the Database Class

 

The following code loads and initializes the database class based on your configuration settings:

$this->load->database();

Once loaded the class is ready to be used as described below.

 

Note: If all your pages require database access you can connect automatically. See the connecting page for details.

 

Standard Query With Multiple Results (Object Version)

$query = $this->db->query('SELECT name, title, email FROM my_table');

foreach ($query->result() as $row)
{
    echo $row->title;
    echo $row->name;
    echo $row->email;
}

echo 'Total Results: ' . $query->num_rows();

The above result() function returns an array of objects. Example: $row->title

 

Standard Query With Multiple Results (Array Version)

$query = $this->db->query('SELECT name, title, email FROM my_table');

foreach ($query->result_array() as $row)
{
    echo $row['title'];
    echo $row['name'];
    echo $row['email'];
}

The above result_array() function returns an array of standard array indexes. Example: $row['title']

 

Testing for Results

 

If you run queries that might not produce a result, you are encouraged to test for a result first using the num_rows() function:

$query = $this->db->query("YOUR QUERY");

if ($query->num_rows() > 0)
{
   foreach ($query->result() as $row)
   {
      echo $row->title;
      echo $row->name;
      echo $row->body;
   }
}

Standard Query With Single Result

$query = $this->db->query('SELECT name FROM my_table LIMIT 1');

$row = $query->row();
echo $row->name;

The above row() function returns an object. Example: $row->name

 

Standard Query With Single Result (Array version)

$query = $this->db->query('SELECT name FROM my_table LIMIT 1');

$row = $query->row_array();
echo $row['name'];

The above row_array() function returns an array. Example: $row['name']

 

Standard Insert

$sql = "INSERT INTO mytable (title, name)
        VALUES (".$this->db->escape($title).", ".$this->db->escape($name).")";

$this->db->query($sql);

echo $this->db->affected_rows();

Active Record Query

 

The Active Record Pattern gives you a simplified means of retrieving data:

$query = $this->db->get('table_name');

foreach ($query->result() as $row)
{
    echo $row->title;
}

The above get() function retrieves all the results from the supplied table. The Active Record class contains a full compliment of functions for working with data.

 

Active Record Insert

$data = array(
               'title' => $title,
               'name' => $name,
               'date' => $date
            );

$this->db->insert('mytable', $data);

// Produces: INSERT INTO mytable (title, name, date) VALUES ('{$title}', '{$name}', '{$date}')