summaryrefslogtreecommitdiffstats
path: root/system/database/drivers/sqlite3/sqlite3_forge.php
blob: 4019a95234e254b290e6233a06cf7dcf720e2040 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
<?php
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP
 *
 * This content is released under the MIT License (MIT)
 *
 * Copyright (c) 2014 - 2019, British Columbia Institute of Technology
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @package	CodeIgniter
 * @author	EllisLab Dev Team
 * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
 * @copyright	Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
 * @license	https://opensource.org/licenses/MIT	MIT License
 * @link	https://codeigniter.com
 * @since	Version 3.0.0
 * @filesource
 */
defined('BASEPATH') OR exit('No direct script access allowed');

/**
 * SQLite3 Forge Class
 *
 * @category	Database
 * @author	Andrey Andreev
 * @link	https://codeigniter.com/user_guide/database/
 */
class CI_DB_sqlite3_forge extends CI_DB_forge {

	/**
	 * UNSIGNED support
	 *
	 * @var	bool|array
	 */
	protected $_unsigned		= FALSE;

	/**
	 * NULL value representation in CREATE/ALTER TABLE statements
	 *
	 * @var	string
	 */
	protected $_null		= 'NULL';

	// --------------------------------------------------------------------

	/**
	 * Class constructor
	 *
	 * @param	object	&$db	Database object
	 * @return	void
	 */
	public function __construct(&$db)
	{
		parent::__construct($db);

		if (version_compare($this->db->version(), '3.3', '<'))
		{
			$this->_create_table_if = FALSE;
			$this->_drop_table_if   = FALSE;
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Create database
	 *
	 * @param	string	$db_name
	 * @return	bool
	 */
	public function create_database($db_name)
	{
		// In SQLite, a database is created when you connect to the database.
		// We'll return TRUE so that an error isn't generated
		return TRUE;
	}

	// --------------------------------------------------------------------

	/**
	 * Drop database
	 *
	 * @param	string	$db_name	(ignored)
	 * @return	bool
	 */
	public function drop_database($db_name)
	{
		// In SQLite, a database is dropped when we delete a file
		if (file_exists($this->db->database))
		{
			// We need to close the pseudo-connection first
			$this->db->close();
			if ( ! @unlink($this->db->database))
			{
				return $this->db->db_debug ? $this->db->display_error('db_unable_to_drop') : FALSE;
			}
			elseif ( ! empty($this->db->data_cache['db_names']))
			{
				$key = array_search(strtolower($this->db->database), array_map('strtolower', $this->db->data_cache['db_names']), TRUE);
				if ($key !== FALSE)
				{
					unset($this->db->data_cache['db_names'][$key]);
				}
			}

			return TRUE;
		}

		return $this->db->db_debug ? $this->db->display_error('db_unable_to_drop') : FALSE;
	}

	// --------------------------------------------------------------------

	/**
	 * ALTER TABLE
	 *
	 * @todo	implement drop_column(), modify_column()
	 * @param	string	$alter_type	ALTER type
	 * @param	string	$table		Table name
	 * @param	mixed	$field		Column definition
	 * @return	string|string[]
	 */
	protected function _alter_table($alter_type, $table, $field)
	{
		if ($alter_type === 'DROP' OR $alter_type === 'CHANGE')
		{
			// drop_column():
			//	BEGIN TRANSACTION;
			//	CREATE TEMPORARY TABLE t1_backup(a,b);
			//	INSERT INTO t1_backup SELECT a,b FROM t1;
			//	DROP TABLE t1;
			//	CREATE TABLE t1(a,b);
			//	INSERT INTO t1 SELECT a,b FROM t1_backup;
			//	DROP TABLE t1_backup;
			//	COMMIT;

			return FALSE;
		}

		return parent::_alter_table($alter_type, $table, $field);
	}

	// --------------------------------------------------------------------

	/**
	 * Process column
	 *
	 * @param	array	$field
	 * @return	string
	 */
	protected function _process_column($field)
	{
		return $this->db->escape_identifiers($field['name'])
			.' '.$field['type']
			.$field['auto_increment']
			.$field['null']
			.$field['unique']
			.$field['default'];
	}

	// --------------------------------------------------------------------

	/**
	 * Field attribute TYPE
	 *
	 * Performs a data type mapping between different databases.
	 *
	 * @param	array	&$attributes
	 * @return	void
	 */
	protected function _attr_type(&$attributes)
	{
		switch (strtoupper($attributes['TYPE']))
		{
			case 'ENUM':
			case 'SET':
				$attributes['TYPE'] = 'TEXT';
				return;
			default: return;
		}
	}

	// --------------------------------------------------------------------

	/**
	 * Field attribute AUTO_INCREMENT
	 *
	 * @param	array	&$attributes
	 * @param	array	&$field
	 * @return	void
	 */
	protected function _attr_auto_increment(&$attributes, &$field)
	{
		if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE && stripos($field['type'], 'int') !== FALSE)
		{
			$field['type'] = 'INTEGER PRIMARY KEY';
			$field['default'] = '';
			$field['null'] = '';
			$field['unique'] = '';
			$field['auto_increment'] = ' AUTOINCREMENT';

			$this->primary_keys = array();
		}
	}

}