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Diffstat (limited to 'user_guide/database/forge.html')
| -rw-r--r-- | user_guide/database/forge.html | 466 |
1 files changed, 233 insertions, 233 deletions
diff --git a/user_guide/database/forge.html b/user_guide/database/forge.html index 3feb487df..409ca2771 100644 --- a/user_guide/database/forge.html +++ b/user_guide/database/forge.html @@ -1,234 +1,234 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
-<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
-<head>
-
-<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-<title>Database Forge Class : CodeIgniter User Guide</title>
-
-<style type='text/css' media='all'>@import url('../userguide.css');</style>
-<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' />
-
-<script type="text/javascript" src="../nav/nav.js"></script>
-<script type="text/javascript" src="../nav/prototype.lite.js"></script>
-<script type="text/javascript" src="../nav/moo.fx.js"></script>
-<script type="text/javascript" src="../nav/user_guide_menu.js"></script>
-
-<meta http-equiv='expires' content='-1' />
-<meta http-equiv= 'pragma' content='no-cache' />
-<meta name='robots' content='all' />
-<meta name='author' content='ExpressionEngine Dev Team' />
-<meta name='description' content='CodeIgniter User Guide' />
-
-</head>
-<body>
-
-<!-- START NAVIGATION -->
-<div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div>
-<div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle_darker.jpg" width="154" height="43" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div>
-<div id="masthead">
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td><h1>CodeIgniter User Guide Version 1.7</h1></td>
-<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td>
-</tr>
-</table>
-</div>
-<!-- END NAVIGATION -->
-
-
-<!-- START BREADCRUMB -->
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td id="breadcrumb">
-<a href="http://codeigniter.com/">CodeIgniter Home</a> ›
-<a href="../index.html">User Guide Home</a> ›
-<a href="index.html">Database Library</a> ›
-Database Forge Class
-</td>
-<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="codeigniter.com/user_guide/" />Search User Guide <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" /> <input type="submit" class="submit" name="sa" value="Go" /></form></td>
-</tr>
-</table>
-<!-- END BREADCRUMB -->
-
-
-<br clear="all" />
-
-
-<!-- START CONTENT -->
-<div id="content">
-
-<h1>Database Forge Class</h1>
-
-<p>The Database Forge Class contains functions that help you manage your database.</p>
-
-<h3>Table of Contents</h3>
-
-<ul>
-<li><a href="#init">Initializing the Forge Class</a></li>
-<li><a href="#create">Creating a Database</a></li>
-<li><a href="#drop">Dropping a Database</a></li>
-<li><a href="#add_field">Adding Fields</a></li>
-<li><a href="#add_key">Adding Keys</a></li>
-<li><a href="#create_table">Creating a Table</a></li>
-<li><a href="#drop_table">Dropping a Table</a></li>
-<li><a href="#rename_table">Renaming a Table</a></li>
-<li><a href="#modifying_tables">Modifying a Table</a></li>
-</ul>
-
-
-<h2><a name="init"></a>Initializing the Forge Class</h2>
-
-<p class="important"><strong>Important:</strong> In order to initialize the Forge class, your database driver must
-already be running, since the forge class relies on it.</p>
-
-<p>Load the Forge Class as follows:</p>
-
-<code>$this->load->dbforge()</code>
-
-<p>Once initialized you will access the functions using the <dfn>$this->dbforge</dfn> object:</p>
-
-<code>$this->dbforge->some_function()</code>
-<h2><a name="create"></a>$this->dbforge->create_database('db_name')</h2>
-
-<p>Permits you to create the database specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p>
-
-<code>if ($this->dbforge->create_database('my_db'))<br />
-{<br />
- echo 'Database created!';<br />
-}</code>
-
-
-
-
-<h2><a name="drop"></a>$this->dbforge->drop_database('db_name')</h2>
-
-<p>Permits you to drop the database specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p>
-
-<code>if ($this->dbforge->drop_database('my_db'))<br />
-{<br />
- echo 'Database deleted!';<br />
-}</code>
-
-
-<h1>Creating and Dropping Tables</h1>
-<p>There are several things you may wish to do when creating tables. Add fields, add keys to the table, alter columns. CodeIgniter provides a mechanism for this.</p>
-<h2><a name="add_field" id="add_field"></a>Adding fields</h2>
-<p>Fields are created via an associative array. Within the array you must include a 'type' key that relates to the datatype of the field. For example, INT, VARCHAR, TEXT, etc. Many datatypes (for example VARCHAR) also require a 'constraint' key.</p>
-<p><code>$fields = array(<br />
- 'users' => array(<br />
- 'type' => 'VARCHAR',<br />
- 'constraint' => '100',<br />
- ),<br />
- );<br />
- <br />
-// will translate to "users VARCHAR(100)" when the field is added.</code></p>
-<p>Additionally, the following key/values can be used:</p>
-<ul>
- <li>unsigned/true : to generate "UNSIGNED" in the field definition.</li>
- <li>default/value : to generate a default value in the field definition.</li>
- <li>null/true : to generate "NULL" in the field definition. Without this, the field will default to "NOT NULL".</li>
- <li>auto_increment/true : generates an auto_increment flag on the field. Note that the field type must be a type that supports this, such as integer.</li>
- </ul>
-<p><code>$fields = array(<br />
- 'blog_id' => array(<br />
- 'type' => 'INT',<br />
- 'constraint' => 5, <br />
- 'unsigned' => TRUE,<br />
- 'auto_increment' => TRUE<br />
- ),<br />
- 'blog_title' => array(<br />
- 'type' => 'VARCHAR',<br />
- 'constraint' => '100',<br />
- ),<br />
- 'blog_author' => array(<br />
- 'type' =>'VARCHAR',<br />
- 'constraint' => '100',<br />
- 'default' => 'King of Town',<br />
- ),<br />
- 'blog_description' => array(<br />
- 'type' => 'TEXT',<br />
- 'null' => TRUE,<br />
- ),<br />
- );<br />
-</code></p>
-<p>After the fields have been defined, they can be added using <dfn>$this->dbforge->add_field($fields);</dfn> followed by a call to the <dfn>create_table()</dfn> function.</p>
-<h3>$this->dbforge->add_field()</h3>
-<p>The add fields function will accept the above array.</p>
-<h3>Passing strings as fields</h3>
-<p>If you know exactly how you want a field to be created, you can pass the string into the field definitions with add_field()</p>
-<p><code>$this->dbforge->add_field("label varchar(100) NOT NULL DEFAULT 'default label'");</code></p>
-<p class="important">Note: Multiple calls to <dfn>add_field()</dfn> are cumulative.</p>
-<h3>Creating an id field</h3>
-<p>There is a special exception for creating id fields. A field with type id will automatically be assinged as an INT(9) auto_incrementing Primary Key.</p>
-<p><code>$this->dbforge->add_field('id');<br />
- // gives id INT(9) NOT NULL AUTO_INCREMENT</code></p>
-<h2><a name="add_key" id="add_key"></a>Adding Keys</h2>
-<p>Generally speaking, you'll want your table to have Keys. This is accomplished with <dfn>$this->dbforge->add_key('field')</dfn>. An optional second parameter set to TRUE will make it a primary key. Note that <dfn>add_key()</dfn> must be followed by a call to <dfn>create_table()</dfn>.</p>
-<p>Multiple column non-primary keys must be sent as an array. Sample output below is for MySQL.</p>
-<p><code>$this->dbforge->add_key('blog_id', TRUE);<br />
- // gives PRIMARY KEY `blog_id` (`blog_id`)<br />
- <br />
- $this->dbforge->add_key('blog_id', TRUE);<br />
- $this->dbforge->add_key('site_id', TRUE);<br />
- // gives PRIMARY KEY `blog_id_site_id` (`blog_id`, `site_id`)<br />
- <br />
- $this->dbforge->add_key('blog_name');<br />
- // gives KEY `blog_name` (`blog_name`)<br />
- <br />
- $this->dbforge->add_key(array('blog_name', 'blog_label'));<br />
- // gives KEY `blog_name_blog_label` (`blog_name`, `blog_label`)</code></p>
-<h2><a name="create_table" id="create_table"></a>Creating a table</h2>
-<p>After fields and keys have been declared, you can create a new table with</p>
-<p><code>$this->dbforge->create_table('table_name');<br />
-// gives CREATE TABLE table_name</code></p>
-<p>An optional second parameter set to TRUE adds an "IF NOT EXISTS" clause into the definition</p>
-<p><code>$this->dbforge->create_table('table_name', TRUE);<br />
-// gives CREATE TABLE IF NOT EXISTS table_name</code></p>
-<h2><a name="drop_table" id="drop_table"></a>Dropping a table</h2>
-<p>Executes a DROP TABLE sql</p>
-<p><code>$this->dbforge->drop_table('table_name');<br />
- // gives DROP TABLE IF EXISTS table_name</code></p>
-<h2><a name="rename_table" id="rename_table"></a>Renaming a table</h2>
-<p>Executes a TABLE rename</p>
-<p><code>$this->dbforge->rename_table('old_table_name', 'new_table_name');<br />
- // gives ALTER TABLE old_table_name RENAME TO new_table_name</code></p>
-<h1><a name="modifying_tables" id="modifying_tables"></a>Modifying Tables</h1>
-<h2>$this->dbforge->add_column()</h2>
-<p>The add_column() function is used to modify an existing table. It accepts the same field array as above, and can be used for an unlimited number of additional fields.</p>
-<p><code>$fields = array(<br />
- 'preferences' => array('type' => 'TEXT')<br />
-);<br />
-$this->dbforge->add_column('table_name', $fields);<br />
-<br />
-// gives ALTER TABLE table_name ADD preferences TEXT</code></p>
-<h2>$this->dbforge->drop_column()</h2>
-<p>Used to remove a column from a table. </p>
-<p><code>$this->dbforge->drop_column('table_name', 'column_to_drop');</code></p>
-<h2>$this->dbforge->modify_column()</h2>
-<p>The usage of this function is identical to add_column(), except it alters an existing column rather than adding a new one. In order to use it you must add a "name" key into the field defining array.</p>
-<p><code>$fields = array(<br />
- 'old_name' => array(<br />
- 'name' => 'new_name',<br />
- 'type' => 'TEXT',<br />
- ),<br />
-);<br />
-$this->dbforge->modify_column('table_name', $fields);<br />
- <br />
- // gives ALTER TABLE table_name CHANGE old_name new_name TEXT </code></p>
-<p> </p>
-</div>
-<!-- END CONTENT -->
-
-
-<div id="footer">
-<p>
-Previous Topic: <a href="caching.html">DB Caching Class</a>
- ·
-<a href="#top">Top of Page</a> ·
-<a href="../index.html">User Guide Home</a> ·
-Next Topic: <a href="utilities.html">Database Utilities Class</a><a href="../libraries/email.html"></a></p>
-<p><a href="http://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p>
-</div>
-
-</body>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> +<head> + +<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> +<title>Database Forge Class : CodeIgniter User Guide</title> + +<style type='text/css' media='all'>@import url('../userguide.css');</style> +<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' /> + +<script type="text/javascript" src="../nav/nav.js"></script> +<script type="text/javascript" src="../nav/prototype.lite.js"></script> +<script type="text/javascript" src="../nav/moo.fx.js"></script> +<script type="text/javascript" src="../nav/user_guide_menu.js"></script> + +<meta http-equiv='expires' content='-1' /> +<meta http-equiv= 'pragma' content='no-cache' /> +<meta name='robots' content='all' /> +<meta name='author' content='ExpressionEngine Dev Team' /> +<meta name='description' content='CodeIgniter User Guide' /> + +</head> +<body> + +<!-- START NAVIGATION --> +<div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div> +<div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle_darker.jpg" width="154" height="43" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div> +<div id="masthead"> +<table cellpadding="0" cellspacing="0" border="0" style="width:100%"> +<tr> +<td><h1>CodeIgniter User Guide Version 1.7</h1></td> +<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td> +</tr> +</table> +</div> +<!-- END NAVIGATION --> + + +<!-- START BREADCRUMB --> +<table cellpadding="0" cellspacing="0" border="0" style="width:100%"> +<tr> +<td id="breadcrumb"> +<a href="http://codeigniter.com/">CodeIgniter Home</a> › +<a href="../index.html">User Guide Home</a> › +<a href="index.html">Database Library</a> › +Database Forge Class +</td> +<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="codeigniter.com/user_guide/" />Search User Guide <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" /> <input type="submit" class="submit" name="sa" value="Go" /></form></td> +</tr> +</table> +<!-- END BREADCRUMB --> + + +<br clear="all" /> + + +<!-- START CONTENT --> +<div id="content"> + +<h1>Database Forge Class</h1> + +<p>The Database Forge Class contains functions that help you manage your database.</p> + +<h3>Table of Contents</h3> + +<ul> +<li><a href="#init">Initializing the Forge Class</a></li> +<li><a href="#create">Creating a Database</a></li> +<li><a href="#drop">Dropping a Database</a></li> +<li><a href="#add_field">Adding Fields</a></li> +<li><a href="#add_key">Adding Keys</a></li> +<li><a href="#create_table">Creating a Table</a></li> +<li><a href="#drop_table">Dropping a Table</a></li> +<li><a href="#rename_table">Renaming a Table</a></li> +<li><a href="#modifying_tables">Modifying a Table</a></li> +</ul> + + +<h2><a name="init"></a>Initializing the Forge Class</h2> + +<p class="important"><strong>Important:</strong> In order to initialize the Forge class, your database driver must +already be running, since the forge class relies on it.</p> + +<p>Load the Forge Class as follows:</p> + +<code>$this->load->dbforge()</code> + +<p>Once initialized you will access the functions using the <dfn>$this->dbforge</dfn> object:</p> + +<code>$this->dbforge->some_function()</code> +<h2><a name="create"></a>$this->dbforge->create_database('db_name')</h2> + +<p>Permits you to create the database specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p> + +<code>if ($this->dbforge->create_database('my_db'))<br /> +{<br /> + echo 'Database created!';<br /> +}</code> + + + + +<h2><a name="drop"></a>$this->dbforge->drop_database('db_name')</h2> + +<p>Permits you to drop the database specified in the first parameter. Returns TRUE/FALSE based on success or failure:</p> + +<code>if ($this->dbforge->drop_database('my_db'))<br /> +{<br /> + echo 'Database deleted!';<br /> +}</code> + + +<h1>Creating and Dropping Tables</h1> +<p>There are several things you may wish to do when creating tables. Add fields, add keys to the table, alter columns. CodeIgniter provides a mechanism for this.</p> +<h2><a name="add_field" id="add_field"></a>Adding fields</h2> +<p>Fields are created via an associative array. Within the array you must include a 'type' key that relates to the datatype of the field. For example, INT, VARCHAR, TEXT, etc. Many datatypes (for example VARCHAR) also require a 'constraint' key.</p> +<p><code>$fields = array(<br /> + 'users' => array(<br /> + 'type' => 'VARCHAR',<br /> + 'constraint' => '100',<br /> + ),<br /> + );<br /> + <br /> +// will translate to "users VARCHAR(100)" when the field is added.</code></p> +<p>Additionally, the following key/values can be used:</p> +<ul> + <li>unsigned/true : to generate "UNSIGNED" in the field definition.</li> + <li>default/value : to generate a default value in the field definition.</li> + <li>null/true : to generate "NULL" in the field definition. Without this, the field will default to "NOT NULL".</li> + <li>auto_increment/true : generates an auto_increment flag on the field. Note that the field type must be a type that supports this, such as integer.</li> + </ul> +<p><code>$fields = array(<br /> + 'blog_id' => array(<br /> + 'type' => 'INT',<br /> + 'constraint' => 5, <br /> + 'unsigned' => TRUE,<br /> + 'auto_increment' => TRUE<br /> + ),<br /> + 'blog_title' => array(<br /> + 'type' => 'VARCHAR',<br /> + 'constraint' => '100',<br /> + ),<br /> + 'blog_author' => array(<br /> + 'type' =>'VARCHAR',<br /> + 'constraint' => '100',<br /> + 'default' => 'King of Town',<br /> + ),<br /> + 'blog_description' => array(<br /> + 'type' => 'TEXT',<br /> + 'null' => TRUE,<br /> + ),<br /> + );<br /> +</code></p> +<p>After the fields have been defined, they can be added using <dfn>$this->dbforge->add_field($fields);</dfn> followed by a call to the <dfn>create_table()</dfn> function.</p> +<h3>$this->dbforge->add_field()</h3> +<p>The add fields function will accept the above array.</p> +<h3>Passing strings as fields</h3> +<p>If you know exactly how you want a field to be created, you can pass the string into the field definitions with add_field()</p> +<p><code>$this->dbforge->add_field("label varchar(100) NOT NULL DEFAULT 'default label'");</code></p> +<p class="important">Note: Multiple calls to <dfn>add_field()</dfn> are cumulative.</p> +<h3>Creating an id field</h3> +<p>There is a special exception for creating id fields. A field with type id will automatically be assinged as an INT(9) auto_incrementing Primary Key.</p> +<p><code>$this->dbforge->add_field('id');<br /> + // gives id INT(9) NOT NULL AUTO_INCREMENT</code></p> +<h2><a name="add_key" id="add_key"></a>Adding Keys</h2> +<p>Generally speaking, you'll want your table to have Keys. This is accomplished with <dfn>$this->dbforge->add_key('field')</dfn>. An optional second parameter set to TRUE will make it a primary key. Note that <dfn>add_key()</dfn> must be followed by a call to <dfn>create_table()</dfn>.</p> +<p>Multiple column non-primary keys must be sent as an array. Sample output below is for MySQL.</p> +<p><code>$this->dbforge->add_key('blog_id', TRUE);<br /> + // gives PRIMARY KEY `blog_id` (`blog_id`)<br /> + <br /> + $this->dbforge->add_key('blog_id', TRUE);<br /> + $this->dbforge->add_key('site_id', TRUE);<br /> + // gives PRIMARY KEY `blog_id_site_id` (`blog_id`, `site_id`)<br /> + <br /> + $this->dbforge->add_key('blog_name');<br /> + // gives KEY `blog_name` (`blog_name`)<br /> + <br /> + $this->dbforge->add_key(array('blog_name', 'blog_label'));<br /> + // gives KEY `blog_name_blog_label` (`blog_name`, `blog_label`)</code></p> +<h2><a name="create_table" id="create_table"></a>Creating a table</h2> +<p>After fields and keys have been declared, you can create a new table with</p> +<p><code>$this->dbforge->create_table('table_name');<br /> +// gives CREATE TABLE table_name</code></p> +<p>An optional second parameter set to TRUE adds an "IF NOT EXISTS" clause into the definition</p> +<p><code>$this->dbforge->create_table('table_name', TRUE);<br /> +// gives CREATE TABLE IF NOT EXISTS table_name</code></p> +<h2><a name="drop_table" id="drop_table"></a>Dropping a table</h2> +<p>Executes a DROP TABLE sql</p> +<p><code>$this->dbforge->drop_table('table_name');<br /> + // gives DROP TABLE IF EXISTS table_name</code></p> +<h2><a name="rename_table" id="rename_table"></a>Renaming a table</h2> +<p>Executes a TABLE rename</p> +<p><code>$this->dbforge->rename_table('old_table_name', 'new_table_name');<br /> + // gives ALTER TABLE old_table_name RENAME TO new_table_name</code></p> +<h1><a name="modifying_tables" id="modifying_tables"></a>Modifying Tables</h1> +<h2>$this->dbforge->add_column()</h2> +<p>The add_column() function is used to modify an existing table. It accepts the same field array as above, and can be used for an unlimited number of additional fields.</p> +<p><code>$fields = array(<br /> + 'preferences' => array('type' => 'TEXT')<br /> +);<br /> +$this->dbforge->add_column('table_name', $fields);<br /> +<br /> +// gives ALTER TABLE table_name ADD preferences TEXT</code></p> +<h2>$this->dbforge->drop_column()</h2> +<p>Used to remove a column from a table. </p> +<p><code>$this->dbforge->drop_column('table_name', 'column_to_drop');</code></p> +<h2>$this->dbforge->modify_column()</h2> +<p>The usage of this function is identical to add_column(), except it alters an existing column rather than adding a new one. In order to use it you must add a "name" key into the field defining array.</p> +<p><code>$fields = array(<br /> + 'old_name' => array(<br /> + 'name' => 'new_name',<br /> + 'type' => 'TEXT',<br /> + ),<br /> +);<br /> +$this->dbforge->modify_column('table_name', $fields);<br /> + <br /> + // gives ALTER TABLE table_name CHANGE old_name new_name TEXT </code></p> +<p> </p> +</div> +<!-- END CONTENT --> + + +<div id="footer"> +<p> +Previous Topic: <a href="caching.html">DB Caching Class</a> + · +<a href="#top">Top of Page</a> · +<a href="../index.html">User Guide Home</a> · +Next Topic: <a href="utilities.html">Database Utilities Class</a><a href="../libraries/email.html"></a></p> +<p><a href="http://codeigniter.com">CodeIgniter</a> · Copyright © 2006-2008 · <a href="http://ellislab.com/">Ellislab, Inc.</a></p> +</div> + +</body> </html>
\ No newline at end of file |