Refactored DB Forge
- PDO subdrivers are isolated from each other now.
- Added compatibility for pretty much all of the features, for every DB platform.
- Unified the way that stuff works in general.
- Fixes issue #1005.
diff --git a/system/database/DB_forge.php b/system/database/DB_forge.php
index f46237e..d8ecefe 100644
--- a/system/database/DB_forge.php
+++ b/system/database/DB_forge.php
@@ -36,6 +36,13 @@
abstract class CI_DB_forge {
/**
+ * Database object
+ *
+ * @var object
+ */
+ public $db;
+
+ /**
* Fields data
*
* @var array
@@ -80,23 +87,68 @@
protected $_drop_database = 'DROP DATABASE %s';
/**
- * DROP TABLE statement
+ * CREATE TABLE statement
*
* @var string
*/
- protected $_drop_table = 'DROP TABLE IF EXISTS %s';
+ protected $_create_table = "%s %s (%s\n)";
+
+ /**
+ * CREATE TABLE IF statement
+ *
+ * @var string
+ */
+ protected $_create_table_if = 'CREATE TABLE IF NOT EXISTS';
+
+ /**
+ * CREATE TABLE keys flag
+ *
+ * Whether table keys are created from within the
+ * CREATE TABLE statement.
+ *
+ * @var bool
+ */
+ protected $_create_table_keys = FALSE;
+
+ /**
+ * DROP TABLE IF EXISTS statement
+ *
+ * @var string
+ */
+ protected $_drop_table_if = 'DROP TABLE IF EXISTS';
/**
* RENAME TABLE statement
*
* @var string
*/
- protected $_rename_table = 'ALTER TABLE %s RENAME TO %s';
+ protected $_rename_table = 'ALTER TABLE %s RENAME TO %s;';
+
+ /**
+ * UNSIGNED support
+ *
+ * @var bool|array
+ */
+ protected $_unsigned = TRUE;
+
+ /**
+ * NULL value representatin in CREATE/ALTER TABLE statements
+ *
+ * @var string
+ */
+ protected $_null = '';
+
+ /**
+ * DEFAULT value representation in CREATE/ALTER TABLE statements
+ *
+ * @var string
+ */
+ protected $_default = ' DEFAULT ';
// --------------------------------------------------------------------
/**
- * Constructor
+ * Class constructor
*
* @return void
*/
@@ -113,7 +165,7 @@
/**
* Create database
*
- * @param string the database name
+ * @param string $db_name
* @return bool
*/
public function create_database($db_name)
@@ -140,7 +192,7 @@
/**
* Drop database
*
- * @param string the database name
+ * @param string $db_name
* @return bool
*/
public function drop_database($db_name)
@@ -176,25 +228,25 @@
/**
* Add Key
*
- * @param string key
- * @param string type
+ * @param string $key
+ * @param bool $primary
* @return object
*/
public function add_key($key = '', $primary = FALSE)
{
- if ($primary && is_array($key))
+ if (empty($key))
+ {
+ show_error('Key information is required for that operation.');
+ }
+
+ if (is_array($key))
{
foreach ($key as $one)
{
$this->add_key($one, $primary);
}
- return;
- }
-
- if ($key === '')
- {
- show_error('Key information is required for that operation.');
+ return $this;
}
if ($primary === TRUE)
@@ -214,12 +266,12 @@
/**
* Add Field
*
- * @param string collation
+ * @param array $field
* @return object
*/
public function add_field($field = '')
{
- if ($field === '')
+ if (empty($field))
{
show_error('Field information is required.');
}
@@ -261,8 +313,8 @@
/**
* Create Table
*
- * @param string $table = ''
- * @param bool $if_not_exists = FALSE
+ * @param string $table Table name
+ * @param bool $if_not_exists Whether to add IF NOT EXISTS condition
* @return bool
*/
public function create_table($table = '', $if_not_exists = FALSE)
@@ -271,51 +323,129 @@
{
show_error('A table name is required for that operation.');
}
+ else
+ {
+ $table = $this->db->dbprefix.$table;
+ }
if (count($this->fields) === 0)
{
show_error('Field information is required.');
}
- $sql = $this->_create_table($this->db->dbprefix.$table, $this->fields, $this->primary_keys, $this->keys, $if_not_exists);
- $this->_reset();
+ $sql = $this->_create_table($table, $if_not_exists);
if (is_bool($sql))
{
- return $sql;
+ $this->_reset();
+ if ($sql === FALSE)
+ {
+ return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
+ }
}
- if (($result = $this->db->query($sql)) !== FALSE && ! empty($this->db->data_cache['table_names']))
+ if (($result = $this->db->query($sql)) !== FALSE)
{
- $this->db->data_cache['table_names'][] = $this->db->dbprefix.$table;
+ empty($this->db->data_cache['table_names']) OR $this->db->data_cache['table_names'][] = $table;
+
+ // Most databases don't support creating indexes from within the CREATE TABLE statement
+ if ( ! empty($this->keys))
+ {
+ for ($i = 0, $sqls = $this->_process_indexes($table), $c = count($sqls); $i < $c; $i++)
+ {
+ $this->db->query($sqls[$i]);
+ }
+ }
}
+ $this->_reset();
return $result;
}
// --------------------------------------------------------------------
/**
+ * Create Table
+ *
+ * @param string $table Table name
+ * @param bool $if_not_exists Whether to add 'IF NOT EXISTS' condition
+ * @return mixed
+ */
+ protected function _create_table($table, $if_not_exists)
+ {
+ if ($if_not_exists === TRUE && $this->_create_table_if === FALSE)
+ {
+ if ($this->db->table_exists($table))
+ {
+ return TRUE;
+ }
+ else
+ {
+ $if_not_exists = FALSE;
+ }
+ }
+
+ $sql = ($if_not_exists)
+ ? sprintf($this->_create_table_if, $this->db->escape_identifiers($table))
+ : 'CREATE TABLE';
+
+ $columns = $this->_process_fields(TRUE);
+ for ($i = 0, $c = count($columns); $i < $c; $i++)
+ {
+ $columns[$i] = ($columns[$i]['_literal'] !== FALSE)
+ ? "\n\t".$columns[$i]['_literal']
+ : "\n\t".$this->_process_column($columns[$i]);
+ }
+
+ $columns = implode(',', $columns)
+ .$this->_process_primary_keys($table);
+
+ // Are indexes created from within the CREATE TABLE statement? (e.g. in MySQL)
+ if ($this->_create_table_keys === TRUE)
+ {
+ $columns .= $this->_process_indexes();
+ }
+
+ // _create_table will usually have the following format: "%s %s (%s\n)"
+ $sql = sprintf($this->_create_table.';',
+ $sql,
+ $this->db->escape_identifiers($table),
+ $columns
+ );
+
+ return $sql;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Drop Table
*
- * @param string the table name
+ * @param string $table_name Table name
+ * @param bool $if_exists Whether to add an IF EXISTS condition
* @return bool
*/
- public function drop_table($table_name)
+ public function drop_table($table_name, $if_exists = FALSE)
{
if ($table_name === '')
{
return ($this->db->db_debug) ? $this->db->display_error('db_table_name_required') : FALSE;
}
- elseif ($this->_drop_table === FALSE)
+
+ $query = $this->_drop_table($this->db->dbprefix.$table_name, $if_exists);
+ if ($query === FALSE)
{
return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
}
+ elseif ($query === TRUE)
+ {
+ return TRUE;
+ }
- $result = $this->db->query(sprintf($this->_drop_table, $this->db->escape_identifiers($this->db->dbprefix.$table_name)));
+ $query = $this->db->query($query);
// Update table list cache
- if ($result && ! empty($this->db->data_cache['table_names']))
+ if ($query && ! empty($this->db->data_cache['table_names']))
{
$key = array_search(strtolower($this->db->dbprefix.$table_name), array_map('strtolower', $this->db->data_cache['table_names']), TRUE);
if ($key !== FALSE)
@@ -324,7 +454,40 @@
}
}
- return $result;
+ return $query;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Drop Table
+ *
+ * Generates a platform-specific DROP TABLE string
+ *
+ * @param string $table Table name
+ * @param bool $if_exists Whether to add an IF EXISTS condition
+ * @return string
+ */
+ protected function _drop_table($table, $if_exists)
+ {
+ $sql = 'DROP TABLE';
+
+ if ($if_exists)
+ {
+ if ($this->_drop_table_if === FALSE)
+ {
+ if ( ! $this->db->table_exists($table))
+ {
+ return TRUE;
+ }
+ }
+ else
+ {
+ $sql = sprintf($this->_drop_table_if, $this->db->escape_identifiers($table));
+ }
+ }
+
+ return $sql.' '.$this->db->escape_identifiers($table);
}
// --------------------------------------------------------------------
@@ -332,8 +495,8 @@
/**
* Rename Table
*
- * @param string the old table name
- * @param string the new table name
+ * @param string $table_name Old table name
+ * @param string $new_table_name New table name
* @return bool
*/
public function rename_table($table_name, $new_table_name)
@@ -370,32 +533,37 @@
/**
* Column Add
*
- * @param string the table name
- * @param string the column name
- * @param string the column definition
+ * @param string $table Table name
+ * @param array $field Column definition
* @return bool
*/
- public function add_column($table = '', $field = array(), $after_field = '')
+ public function add_column($table = '', $field = array())
{
if ($table === '')
{
show_error('A table name is required for that operation.');
}
- // add field info into field array, but we can only do one at a time
- // so we cycle through
+ // Work-around for literal column definitions
+ if ( ! is_array($field))
+ {
+ $field = array($field);
+ }
+
foreach (array_keys($field) as $k)
{
$this->add_field(array($k => $field[$k]));
+ }
- if (count($this->fields) === 0)
- {
- show_error('Field information is required.');
- }
+ $sqls = $this->_alter_table('ADD', $this->db->dbprefix.$table, $this->_process_fields());
+ $this->_reset();
+ if ($sqls === FALSE)
+ {
+ return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
+ }
- $sql = $this->_alter_table('ADD', $this->db->dbprefix.$table, $this->fields, $after_field);
- $this->_reset();
-
+ for ($i = 0, $c = count($sqls); $i < $c; $i++)
+ {
if ($this->db->query($sql) === FALSE)
{
return FALSE;
@@ -410,8 +578,8 @@
/**
* Column Drop
*
- * @param string the table name
- * @param string the column name
+ * @param string $table Table name
+ * @param string $column_name Column name
* @return bool
*/
public function drop_column($table = '', $column_name = '')
@@ -426,7 +594,13 @@
show_error('A column name is required for that operation.');
}
- return $this->db->query($this->_alter_table('DROP', $this->db->dbprefix.$table, $column_name));
+ $sql = $this->_alter_table('DROP', $this->db->dbprefix.$table, $column_name);
+ if ($sql === FALSE)
+ {
+ return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
+ }
+
+ return $this->db->query($sql);
}
// --------------------------------------------------------------------
@@ -434,8 +608,8 @@
/**
* Column Modify
*
- * @param string $table = ''
- * @param string $field = array() column definition
+ * @param string $table Table name
+ * @param string $field Column definition
* @return bool
*/
public function modify_column($table = '', $field = array())
@@ -445,25 +619,31 @@
show_error('A table name is required for that operation.');
}
- // add field info into field array, but we can only do one at a time
- // so we cycle through
+ // Work-around for literal column definitions
+ if ( ! is_array($field))
+ {
+ $field = array($field);
+ }
+
foreach (array_keys($field) as $k)
{
- // If no name provided, use the current name
- if ( ! isset($field[$k]['name']))
- {
- $field[$k]['name'] = $k;
- }
-
$this->add_field(array($k => $field[$k]));
- if (count($this->fields) === 0)
- {
- show_error('Field information is required.');
- }
+ }
- $sql = $this->_alter_table('CHANGE', $this->db->dbprefix.$table, $this->fields);
- $this->_reset();
+ if (count($this->fields) === 0)
+ {
+ show_error('Field information is required.');
+ }
+ $sqls = $this->_alter_table('CHANGE', $this->db->dbprefix.$table, $this->fields);
+ $this->_reset();
+ if ($sqls === FALSE)
+ {
+ return ($this->db->db_debug) ? $this->db->display_error('db_unsuported_feature') : FALSE;
+ }
+
+ for ($i = 0, $c = count($sqls); $i < $c; $i++)
+ {
if ($this->db->query($sql) === FALSE)
{
return FALSE;
@@ -476,6 +656,331 @@
// --------------------------------------------------------------------
/**
+ * ALTER TABLE
+ *
+ * @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)
+ {
+ $sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' ';
+
+ // DROP has everything it needs now.
+ if ($alter_type === 'DROP')
+ {
+ return $sql.'DROP COLUMN '.$this->db->escape_identifiers($field);
+ }
+
+ $sqls = array();
+ for ($i = 0, $c = count($field), $sql .= $alter_type.' COLUMN '; $i < $c; $i++)
+ {
+ $sqls[] = $sql
+ .($field[$i]['_literal'] !== FALSE ? $field[$i]['_literal'] : $this->_process_column($field[$i]));
+ }
+
+ return $sqls;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Process fields
+ *
+ * @param bool $create_table
+ * @return array
+ */
+ protected function _process_fields($create_table = FALSE)
+ {
+ $fields = array();
+
+ foreach ($this->fields as $key => $attributes)
+ {
+ if (is_int($key) && ! is_array($attributes))
+ {
+ $fields[] = array('_literal' => $attributes);
+ continue;
+ }
+
+ $attributes = array_change_key_case($attributes, CASE_UPPER);
+
+ if ($create_table === TRUE && empty($attributes['TYPE']))
+ {
+ continue;
+ }
+
+ if (isset($attributes['TYPE']))
+ {
+ $this->_attr_type($attributes);
+ $this->_attr_unsigned($attributes, $field);
+ }
+
+ $field = array(
+ 'name' => $key,
+ 'new_name' => isset($attributes['NAME']) ? $attributes['NAME'] : NULL,
+ 'type' => isset($attributes['TYPE']) ? $attributes['TYPE'] : NULL,
+ 'length' => '',
+ 'unsigned' => '',
+ 'null' => '',
+ 'unique' => '',
+ 'default' => '',
+ 'auto_increment' => '',
+ '_literal' => FALSE
+ );
+
+ $this->_attr_default($attributes, $field);
+
+ if (isset($attributes['NULL']))
+ {
+ if ($attributes['NULL'] === TRUE)
+ {
+ $field['null'] = empty($this->_null) ? '' : ' '.$this->_null;
+ }
+ elseif ($create_table === TRUE)
+ {
+ $field['null'] = ' NOT NULL';
+ }
+ }
+
+ $this->_attr_auto_increment($attributes, $field);
+ $this->_attr_unique($attributes, $field);
+
+ if (isset($attributes['TYPE']) && ! empty($attributes['CONSTRAINT']))
+ {
+ switch (strtoupper($attributes['TYPE']))
+ {
+ case 'ENUM':
+ case 'SET':
+ $attributes['CONSTRAINT'] = $this->db->escape($attributes['CONSTRAINT']);
+ default:
+ $field['length'] = is_array($attributes['CONSTRAINT'])
+ ? '('.implode(',', $attributes['CONSTRAINT']).')'
+ : '('.$attributes['CONSTRAINT'].')';
+ break;
+ }
+ }
+
+ $fields[] = $field;
+ }
+
+ return $fields;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Process column
+ *
+ * @param array $field
+ * @return string
+ */
+ protected function _process_column($field)
+ {
+ return $this->db->escape_identifiers($field['name'])
+ .' '.$field['type'].$field['length']
+ .$field['unsigned']
+ .$field['default']
+ .$field['null']
+ .$field['auto_increment']
+ .$field['unique'];
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Field attribute TYPE
+ *
+ * Performs a data type mapping between different databases.
+ *
+ * @param array &$attributes
+ * @return void
+ */
+ protected function _attr_type(&$attributes)
+ {
+ // Usually overriden by drivers
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Field attribute UNSIGNED
+ *
+ * Depending on the _unsigned property value:
+ *
+ * - TRUE will always set $field['unsigned'] to 'UNSIGNED'
+ * - FALSE will always set $field['unsigned'] to ''
+ * - array(TYPE) will set $field['unsigned'] to 'UNSIGNED',
+ * if $attributes['TYPE'] is found in the array
+ * - array(TYPE => UTYPE) will change $field['type'],
+ * from TYPE to UTYPE in case of a match
+ *
+ * @param array &$attributes
+ * @param array &$field
+ * @return void
+ */
+ protected function _attr_unsigned(&$attributes, &$field)
+ {
+ if (empty($attributes['UNSIGNED']) OR $attributes['UNSIGNED'] !== TRUE)
+ {
+ return;
+ }
+
+ // Reset the attribute in order to avoid issues if we do type conversion
+ $attributes['UNSIGNED'] = FALSE;
+
+ if (is_array($this->_unsigned))
+ {
+ foreach (array_keys($this->_unsigned) as $key)
+ {
+ if (is_int($key) && strcasecmp($attributes['TYPE'], $this->_unsigned[$key]) === 0)
+ {
+ $field['unsigned'] = ' UNSIGNED';
+ return;
+ }
+ elseif (is_string($key) && strcasecmp($attributes['TYPE'], $key) === 0)
+ {
+ $field['type'] = $key;
+ return;
+ }
+ }
+
+ return;
+ }
+
+ $field['unsigned'] = ($this->_unsigned === TRUE) ? ' UNSIGNED' : '';
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Field attribute DEFAULT
+ *
+ * @param array &$attributes
+ * @param array &$field
+ * @return void
+ */
+ protected function _attr_default(&$attributes, &$field)
+ {
+ if ($this->_default === FALSE)
+ {
+ return;
+ }
+
+ if (array_key_exists('DEFAULT', $attributes))
+ {
+ if ($attributes['DEFAULT'] === NULL)
+ {
+ $field['default'] = empty($this->_null) ? '' : $this->_default.$this->_null;
+
+ // Override the NULL attribute if that's our default
+ $attributes['NULL'] = NULL;
+ $field['null'] = empty($this->_null) ? '' : ' '.$this->_null;
+ }
+ else
+ {
+ $field['default'] = $this->_default.$this->db->escape($attributes['DEFAULT']);
+ }
+ }
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Field attribute UNIQUE
+ *
+ * @param array &$attributes
+ * @param array &$field
+ * @return void
+ */
+ protected function _attr_unique(&$attributes, &$field)
+ {
+ if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+ {
+ $field['unique'] = ' UNIQUE';
+ }
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Field attribute AUTO_INCREMENT
+ *
+ * @param array &$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['auto_increment'] = ' AUTO_INCREMENT';
+ }
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Process primary keys
+ *
+ * @param string $table Table name
+ * @return string
+ */
+ protected function _process_primary_keys($table)
+ {
+ $sql = '';
+
+ for ($i = 0, $c = count($this->primary_keys); $i < $c; $i++)
+ {
+ if ( ! isset($this->fields[$this->primary_keys[$i]]))
+ {
+ unset($this->primary_keys[$i]);
+ }
+ }
+
+ if (count($this->primary_keys) > 0)
+ {
+ $sql .= ",\n\tCONSTRAINT ".$this->db->escape_identifiers('pk_'.$table)
+ .' PRIMARY KEY('.implode(', ', $this->db->escape_identifiers($this->primary_keys)).')';
+ }
+
+ return $sql;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
+ * Process indexes
+ *
+ * @param string $table
+ * @return string
+ */
+ protected function _process_indexes($table = NULL)
+ {
+ $table = $this->db->escape_identifiers($table);
+ $sqls = array();
+
+ for ($i = 0, $c = count($this->keys); $i < $c; $i++)
+ {
+ if ( ! isset($this->fields[$this->keys[$i]]))
+ {
+ unset($this->keys[$i]);
+ continue;
+ }
+
+ is_array($this->keys[$i]) OR $this->keys[$i] = array($this->keys[$i]);
+
+ $sqls[] = 'CREATE INDEX '.$this->db->escape_identifiers(implode('_', $this->keys[$i]))
+ .' ON '.$this->db->escape_identifiers($table)
+ .' ('.implode(', ', $this->db->escape_identifiers($this->keys[$i])).');';
+ }
+
+ return $sqls;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Reset
*
* Resets table creation vars