Resolve formatting differences between DB forge drivers

10 files changed, 209 insertions, 222 deletions

diff --git a/system/database/drivers/cubrid/cubrid_forge.php b/system/database/drivers/cubrid/cubrid_forge.php
index fb9716226..1379e6d3a 100644
--- a/system/database/drivers/cubrid/cubrid_forge.php
+++ b/system/database/drivers/cubrid/cubrid_forge.php
@@ -60,8 +60,10 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '');
+
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
+
+				empty($attributes['NAME']) OR $sql .= $this->db->escape_identifiers($attributes['NAME']).' ';
 
 				if ( ! empty($attributes['TYPE']))
 				{
@@ -69,7 +71,7 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 
 					if ( ! empty($attributes['CONSTRAINT']))
 					{
-						switch ($attributes['TYPE'])
+						switch (strtolower($attributes['TYPE']))
 						{
 							case 'decimal':
 							case 'float':
@@ -98,10 +100,23 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 				}
 			 */
 
-				$sql .= (isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '')
-					.(( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE) ? ' UNIQUE' : '');
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
+
+				if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+				{
+					$sql .= ' UNIQUE';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -142,8 +157,8 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 		// If there is a PK defined
 		if (count($primary_keys) > 0)
 		{
-			$key_name = $this->db->protect_identifiers('pk_'.$table.'_'.implode('_', $primary_keys));
-			$sql .= ",\n\tCONSTRAINT ".$key_name.' PRIMARY KEY('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
+			$key_name = $this->db->escape_identifiers('pk_'.$table.'_'.implode('_', $primary_keys));
+			$sql .= ",\n\tCONSTRAINT ".$key_name.' PRIMARY KEY('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -152,12 +167,12 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 			{
 				if (is_array($key))
 				{
-					$key_name = $this->db->protect_identifiers('idx_'.$table.implode('_', $key));
-					$key = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers('idx_'.$table.implode('_', $key));
+					$key = $this->db->escape_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->protect_identifiers('idx_'.$table.$key);
+					$key_name = $this->db->escape_identifiers('idx_'.$table.$key);
 					$key = array($key_name);
 				}
 
@@ -184,16 +199,16 @@ class CI_DB_cubrid_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->protect_identifiers($fields);
+			return $sql.$this->db->escape_identifiers($fields);
 		}
 
 		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/interbase/interbase_forge.php b/system/database/drivers/interbase/interbase_forge.php
index 5470179a1..166f3875a 100644
--- a/system/database/drivers/interbase/interbase_forge.php
+++ b/system/database/drivers/interbase/interbase_forge.php
@@ -87,7 +87,7 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 	{
 		$sql = 'CREATE TABLE ';
 
-		$sql .= $this->db->protect_identifiers($table)."(";
+		$sql .= $this->db->protect_identifiers($table).'(';
 		$current_field_count = 0;
 
 		foreach ($fields as $field => $attributes)
@@ -97,41 +97,30 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 			// entered the field information, so we'll simply add it to the list
 			if (is_numeric($field))
 			{
-				$sql .= "\n\t$attributes";
+				$sql .= "\n\t".$attributes;
 			}
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
+				empty($attributes['CONSTRAINT']) OR $sql .= '('.$attributes['CONSTRAINT'].')';
 
-				if (array_key_exists('CONSTRAINT', $attributes))
-				{
-					$sql .= '('.$attributes['CONSTRAINT'].')';
-				}
-
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -146,30 +135,23 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$primary_keys = $this->db->escape_identifiers($primary_keys);
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tUNIQUE (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tUNIQUE (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -191,31 +173,11 @@ class CI_DB_interbase_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table)." $alter_type ".$this->db->protect_identifiers($column_name);
-
-		$sql .= " {$column_definition}";
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT \"{$default_value}\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field !== '')
-		{
-			$sql .= ' AFTER ' . $this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
+		return 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name)
+			.' '.$column_definition
+			.($default_value !== '' ? ' DEFAULT "'.$default_value.'"' : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mssql/mssql_forge.php b/system/database/drivers/mssql/mssql_forge.php
index d2a30b20f..3a3528f7b 100644
--- a/system/database/drivers/mssql/mssql_forge.php
+++ b/system/database/drivers/mssql/mssql_forge.php
@@ -151,7 +151,7 @@ class CI_DB_mssql_forge extends CI_DB_forge {
 		return $sql.' '.$column_definition
 			.($default_value != '' ? ' DEFAULT "'.$default_value.'"' : '')
 			.($null === NULL ? ' NULL' : ' NOT NULL')
-			.($after_field != '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field != '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mysql/mysql_forge.php b/system/database/drivers/mysql/mysql_forge.php
index ffd374fbf..0279b9dfa 100644
--- a/system/database/drivers/mysql/mysql_forge.php
+++ b/system/database/drivers/mysql/mysql_forge.php
@@ -60,8 +60,9 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '');
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
+
+				empty($attributes['NAME']) OR ' '.$this->db->protect_identifiers($attributes['NAME']).' ';
 
 				if ( ! empty($attributes['TYPE']))
 				{
@@ -86,10 +87,23 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 					}
 				}
 
-				$sql .= (( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
-					.(isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -123,12 +137,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 			$sql .= 'IF NOT EXISTS ';
 		}
 
-		$sql .= $this->db->protect_identifiers($table).' ('.$this->_process_fields($fields);
+		$sql .= $this->db->escape_identifiers($table).' ('.$this->_process_fields($fields);
 
 		if (count($primary_keys) > 0)
 		{
-			$key_name = $this->db->protect_identifiers(implode('_', $primary_keys));
-			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
+			$key_name = $this->db->escape_identifiers(implode('_', $primary_keys));
+			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -137,12 +151,12 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 			{
 				if (is_array($key))
 				{
-					$key_name = $this->db->protect_identifiers(implode('_', $key));
-					$key = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers(implode('_', $key));
+					$key = $this->db->escape_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers($key);
 					$key = array($key_name);
 				}
 
@@ -169,16 +183,16 @@ class CI_DB_mysql_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->protect_identifiers($fields);
+			return $sql.$this->db->escape_identifiers($fields);
 		}
 
 		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/mysqli/mysqli_forge.php b/system/database/drivers/mysqli/mysqli_forge.php
index b00bfde49..a1f58f0f7 100644
--- a/system/database/drivers/mysqli/mysqli_forge.php
+++ b/system/database/drivers/mysqli/mysqli_forge.php
@@ -60,13 +60,13 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.( ! empty($attributes['NAME']) ? ' '.$this->db->protect_identifiers($attributes['NAME']).' ' : '')
-				;
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
+
+				empty($attributes['NAME']) OR $sql .= ' '.$this->db->protect_identifiers($attributes['NAME']).' ';
 
 				if ( ! empty($attributes['TYPE']))
 				{
-					$sql .=  ' '.$attributes['TYPE'];
+					$sql .= ' '.$attributes['TYPE'];
 
 					if ( ! empty($attributes['CONSTRAINT']))
 					{
@@ -87,10 +87,23 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 					}
 				}
 
-				$sql .= (( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
-					.(isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -128,8 +141,8 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$key_name = $this->db->protect_identifiers(implode('_', $primary_keys));
-			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->protect_identifiers($primary_keys)).')';
+			$key_name = $this->db->escape_identifiers(implode('_', $primary_keys));
+			$sql .= ",\n\tPRIMARY KEY ".$key_name.' ('.implode(', ', $this->db->escape_identifiers($primary_keys)).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
@@ -138,12 +151,12 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 			{
 				if (is_array($key))
 				{
-					$key_name = $this->db->protect_identifiers(implode('_', $key));
-					$key = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers(implode('_', $key));
+					$key = $this->db->escape_identifiers($key);
 				}
 				else
 				{
-					$key_name = $this->db->protect_identifiers($key);
+					$key_name = $this->db->escape_identifiers($key);
 					$key = array($key_name);
 				}
 
@@ -170,16 +183,16 @@ class CI_DB_mysqli_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
 		{
-			return $sql.$this->db->protect_identifiers($fields);
+			return $sql.$this->db->escape_identifiers($fields);
 		}
 
 		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/oci8/oci8_forge.php b/system/database/drivers/oci8/oci8_forge.php
index 837e7eaad..4fd3dc4a5 100644
--- a/system/database/drivers/oci8/oci8_forge.php
+++ b/system/database/drivers/oci8/oci8_forge.php
@@ -73,11 +73,22 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field).' '.$attributes['TYPE']
-					.((isset($attributes['UNSINGED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
-					.(isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.((isset($attributes['NULL']) && $attributes['NULL'] === TRUE) ? '' : ' NOT NULL')
-					.(isset($attributes['CONSTRAINT']) ? ' CONSTRAINT '.$attributes['CONSTRAINT'] : '');
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
+
+				if (isset($attributes['UNSINGED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= (isset($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? '' : ' NOT NULL';
+
+				empty($attributes['CONSTRAINT']) OR ' CONSTRAINT '.$attributes['CONSTRAINT'];
 			}
 
 			// don't add a comma on the end of the last field
@@ -89,7 +100,7 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
+			$primary_keys = $this->db->escape_identifiers($primary_keys);
 			$sql .= ",\n\tCONSTRAINT ".$table.' PRIMARY KEY ('.implode(', ', $primary_keys).')';
 		}
 
@@ -97,14 +108,9 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				$sql .= ",\n\tUNIQUE COLUMNS (".implode(', ', $key).')';
 			}
@@ -132,7 +138,7 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
 	{
-		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' '.$this->db->protect_identifiers($column_name);
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -143,7 +149,7 @@ class CI_DB_oci8_forge extends CI_DB_forge {
 		return $sql.' '.$column_definition
 			.($default_value !== '' ? ' DEFAULT "'.$default_value.'"' : '')
 			.($null === NULL ? ' NULL' : ' NOT NULL')
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 
 	}
 
diff --git a/system/database/drivers/pdo/pdo_forge.php b/system/database/drivers/pdo/pdo_forge.php
index aee8f718a..8ce4513dc 100644
--- a/system/database/drivers/pdo/pdo_forge.php
+++ b/system/database/drivers/pdo/pdo_forge.php
@@ -66,18 +66,16 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			// entered the field information, so we'll simply add it to the list
 			if (is_numeric($field))
 			{
-				$sql .= "\n\t$attributes";
+				$sql .= "\n\t".$attributes;
 			}
 			else
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
-				$numeric    = array('SERIAL', 'INTEGER');
+				$numeric = array('SERIAL', 'INTEGER');
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field);
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
 
-				$sql .=  ' '.$attributes['TYPE'];
-
-				if (array_key_exists('CONSTRAINT', $attributes))
+				if ( ! empty($attributes['CONSTRAINT']))
 				{
 					// Exception for Postgre numeric which not too happy with constraint within those type
 					if ( ! ($this->db->pdodriver === 'pgsql' && in_array($attributes['TYPE'], $numeric)))
@@ -86,26 +84,20 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 					}
 				}
 
-				if (array_key_exists('UNSIGNED', $attributes) && $attributes['UNSIGNED'] === TRUE)
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
 				{
 					$sql .= ' UNSIGNED';
 				}
 
-				if (array_key_exists('DEFAULT', $attributes))
+				if (isset($attributes['DEFAULT']))
 				{
-					$sql .= ' DEFAULT \''.$attributes['DEFAULT'].'\'';
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
 				}
 
-				if (array_key_exists('NULL', $attributes) && $attributes['NULL'] === TRUE)
-				{
-					$sql .= ' NULL';
-				}
-				else
-				{
-					$sql .= ' NOT NULL';
-				}
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
 
-				if (array_key_exists('AUTO_INCREMENT', $attributes) && $attributes['AUTO_INCREMENT'] === TRUE)
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
 				{
 					$sql .= ' AUTO_INCREMENT';
 				}
@@ -120,30 +112,23 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
-			$sql .= ",\n\tPRIMARY KEY (" . implode(', ', $primary_keys) . ")";
+			$primary_keys = $this->db->escape_identifiers($primary_keys);
+			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
 		}
 
 		if (is_array($keys) && count($keys) > 0)
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
-				$sql .= ",\n\tFOREIGN KEY (" . implode(', ', $key) . ")";
+				$sql .= ",\n\tFOREIGN KEY (".implode(', ', $key).')';
 			}
 		}
 
-		$sql .= "\n)";
-
-		return $sql;
+		return $sql."\n)";
 	}
 
 	// --------------------------------------------------------------------
@@ -165,7 +150,7 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $column_name, $column_definition = '', $default_value = '', $null = '', $after_field = '')
 	{
-		$sql = 'ALTER TABLE `'.$this->db->protect_identifiers($table).'` '.$alter_type.' '.$this->db->protect_identifiers($column_name);
+		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name);
 
 		// DROP has everything it needs now.
 		if ($alter_type === 'DROP')
@@ -173,29 +158,10 @@ class CI_DB_pdo_forge extends CI_DB_forge {
 			return $sql;
 		}
 
-		$sql .= " $column_definition";
-
-		if ($default_value !== '')
-		{
-			$sql .= " DEFAULT \"$default_value\"";
-		}
-
-		if ($null === NULL)
-		{
-			$sql .= ' NULL';
-		}
-		else
-		{
-			$sql .= ' NOT NULL';
-		}
-
-		if ($after_field !== '')
-		{
-			return $sql.' AFTER '.$this->db->protect_identifiers($after_field);
-		}
-
-		return $sql;
-
+		return $sql .' '.$column_definition
+			.($default_value !== '' ? " DEFAULT '".$default_value."'" : '')
+			.($null === NULL ? ' NULL' : ' NOT NULL')
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
 	}
 
 }
diff --git a/system/database/drivers/postgre/postgre_forge.php b/system/database/drivers/postgre/postgre_forge.php
index af1c45f9b..98b484bcf 100644
--- a/system/database/drivers/postgre/postgre_forge.php
+++ b/system/database/drivers/postgre/postgre_forge.php
@@ -58,7 +58,7 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 			}
 			else
 			{
-				$sql .= "\n\t".$this->db->protect_identifiers($field);
+				$sql .= "\n\t".$this->db->escape_identifiers($field);
 
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 				$is_unsigned = ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE);
@@ -107,10 +107,19 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 					$sql .= '('.$attributes['CONSTRAINT'].')';
 				}
 
-				$sql .= (isset($attributes['DEFAULT']) ? " DEFAULT '".$attributes['DEFAULT']."'" : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					// Added new attribute to create unqite fields. Also works with MySQL
-					.(( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE) ? ' UNIQUE' : '');
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				// Added new attribute to create unique fields. Also works with MySQL
+				if ( ! empty($attributes['UNIQUE']) && $attributes['UNIQUE'] === TRUE)
+				{
+					$sql .= ' UNIQUE';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -139,23 +148,20 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 	{
 		$sql = 'CREATE TABLE ';
 
-		if ($if_not_exists === TRUE)
+		// PostgreSQL doesn't support IF NOT EXISTS syntax so we check if table exists manually
+		if ($if_not_exists === TRUE && $this->db->table_exists($table))
 		{
-			// PostgreSQL doesn't support IF NOT EXISTS syntax so we check if table exists manually
-			if ($this->db->table_exists($table))
-			{
-				return TRUE;
-			}
+			return TRUE;
 		}
 
 		$sql .= $this->db->escape_identifiers($table).' ('.$this->_process_fields($fields, $primary_keys);
 
 		if (count($primary_keys) > 0)
 		{
-			// Something seems to break when passing an array to protect_identifiers()
+			// Something seems to break when passing an array to escape_identifiers()
 			foreach ($primary_keys as $index => $key)
 			{
-				$primary_keys[$index] = $this->db->protect_identifiers($key);
+				$primary_keys[$index] = $this->db->escape_identifiers($key);
 			}
 
 			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
@@ -167,18 +173,14 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				foreach ($key as $field)
 				{
-					$sql .= 'CREATE INDEX '.$table.'_'.str_replace(array('"', "'"), '', $field).'_index ON '.$table.' ('.$field.'); ';
+					$sql .= "\nCREATE INDEX ".$this->db->escape_identifiers($table.'_'.str_replace(array('"', "'"), '', $field).'_index')
+						.' ON '.$this->db->escape_identifiers($table).' ('.$this->db->escape_identifiers($field).');';
 				}
 			}
 		}
@@ -205,16 +207,16 @@ class CI_DB_postgre_forge extends CI_DB_forge {
 	 */
 	protected function _alter_table($alter_type, $table, $fields, $after_field = '')
  	{
- 		$sql = 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' ';
+ 		$sql = 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' ';
 
  		// DROP has everything it needs now.
  		if ($alter_type === 'DROP')
  		{
- 			return $sql.$this->db->protect_identifiers($fields);
+ 			return $sql.$this->db->escape_identifiers($fields);
  		}
 
  		return $sql.$this->_process_fields($fields)
-			.($after_field !== '' ? ' AFTER '.$this->db->protect_identifiers($after_field) : '');
+			.($after_field !== '' ? ' AFTER '.$this->db->escape_identifiers($after_field) : '');
  	}
 
 }
diff --git a/system/database/drivers/sqlite/sqlite_forge.php b/system/database/drivers/sqlite/sqlite_forge.php
index 25f4bf76d..71eed7df4 100644
--- a/system/database/drivers/sqlite/sqlite_forge.php
+++ b/system/database/drivers/sqlite/sqlite_forge.php
@@ -183,7 +183,7 @@ class CI_DB_sqlite_forge extends CI_DB_forge {
 			return FALSE;
 		}
 
-		return 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' '.$this->db->protect_identifiers($column_name)
+		return 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name)
 			.' '.$column_definition
 			.($default_value != '' ? " DEFAULT '".$default_value."'" : '')
 			// If NOT NULL is specified, the field must have a DEFAULT value other than NULL
diff --git a/system/database/drivers/sqlite3/sqlite3_forge.php b/system/database/drivers/sqlite3/sqlite3_forge.php
index 0a5dc9211..6df361444 100644
--- a/system/database/drivers/sqlite3/sqlite3_forge.php
+++ b/system/database/drivers/sqlite3/sqlite3_forge.php
@@ -111,13 +111,27 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 			{
 				$attributes = array_change_key_case($attributes, CASE_UPPER);
 
-				$sql .= "\n\t".$this->db->protect_identifiers($field)
-					.' '.$attributes['TYPE']
-					.( ! empty($attributes['CONSTRAINT']) ? '('.$attributes['CONSTRAINT'].')' : '')
-					.(( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE) ? ' UNSIGNED' : '')
-					.(isset($attributes['DEFAULT']) ? ' DEFAULT \''.$attributes['DEFAULT'].'\'' : '')
-					.(( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE) ? ' NULL' : ' NOT NULL')
-					.(( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE) ? ' AUTO_INCREMENT' : '');
+				$sql .= "\n\t".$this->db->escape_identifiers($field).' '.$attributes['TYPE'];
+
+				empty($attributes['CONSTRAINT']) OR $sql .= '('.$attributes['CONSTRAINT'].')';
+
+				if ( ! empty($attributes['UNSIGNED']) && $attributes['UNSIGNED'] === TRUE)
+				{
+					$sql .= ' UNSIGNED';
+				}
+
+				if (isset($attributes['DEFAULT']))
+				{
+					$sql .= " DEFAULT '".$attributes['DEFAULT']."'";
+				}
+
+				$sql .= ( ! empty($attributes['NULL']) && $attributes['NULL'] === TRUE)
+					? ' NULL' : ' NOT NULL';
+
+				if ( ! empty($attributes['AUTO_INCREMENT']) && $attributes['AUTO_INCREMENT'] === TRUE)
+				{
+					$sql .= ' AUTO_INCREMENT';
+				}
 			}
 
 			// don't add a comma on the end of the last field
@@ -129,7 +143,7 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 
 		if (count($primary_keys) > 0)
 		{
-			$primary_keys = $this->db->protect_identifiers($primary_keys);
+			$primary_keys = $this->db->escape_identifiers($primary_keys);
 			$sql .= ",\n\tPRIMARY KEY (".implode(', ', $primary_keys).')';
 		}
 
@@ -137,14 +151,9 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 		{
 			foreach ($keys as $key)
 			{
-				if (is_array($key))
-				{
-					$key = $this->db->protect_identifiers($key);
-				}
-				else
-				{
-					$key = array($this->db->protect_identifiers($key));
-				}
+				$key = is_array($key)
+					? $this->db->escape_identifiers($key)
+					: array($this->db->escape_identifiers($key));
 
 				$sql .= ",\n\tUNIQUE (".implode(', ', $key).')';
 			}
@@ -182,7 +191,7 @@ class CI_DB_sqlite3_forge extends CI_DB_forge {
 			return FALSE;
 		}
 
-		return 'ALTER TABLE '.$this->db->protect_identifiers($table).' '.$alter_type.' '.$this->db->protect_identifiers($column_name)
+		return 'ALTER TABLE '.$this->db->escape_identifiers($table).' '.$alter_type.' '.$this->db->escape_identifiers($column_name)
 			.' '.$column_definition
 			.($default_value !== '' ? ' DEFAULT '.$default_value : '')
 			// If NOT NULL is specified, the field must have a DEFAULT value other than NULL