Add a dummy db_select() method to CI_DB_driver and remove it from drivers that don't have such functionality
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index d3359e1..594fcce 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -192,10 +192,24 @@
// --------------------------------------------------------------------
/**
+ * Select database
+ *
+ * This is just a dummy method to allow drivers without such
+ * functionality to not declare it, while others will override it.
+ *
+ * @return bool
+ */
+ public function db_select()
+ {
+ return TRUE;
+ }
+
+ // --------------------------------------------------------------------
+
+ /**
* Set client character set
*
* @param string
- * @param string
* @return bool
*/
public function db_set_charset($charset)
diff --git a/system/database/drivers/cubrid/cubrid_driver.php b/system/database/drivers/cubrid/cubrid_driver.php
index bed3d86..0f9c427 100644
--- a/system/database/drivers/cubrid/cubrid_driver.php
+++ b/system/database/drivers/cubrid/cubrid_driver.php
@@ -159,22 +159,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return resource
- */
- public function db_select()
- {
- // In CUBRID there is no need to select a database as the database
- // is chosen at the connection time.
- // So, to determine if the database is "selected", all we have to
- // do is ping the server and return that value.
- return cubrid_ping($this->conn_id);
- }
-
- // --------------------------------------------------------------------
-
- /**
* Database version number
*
* @return string
diff --git a/system/database/drivers/interbase/interbase_driver.php b/system/database/drivers/interbase/interbase_driver.php
index d8b6ae5..6d33462 100644
--- a/system/database/drivers/interbase/interbase_driver.php
+++ b/system/database/drivers/interbase/interbase_driver.php
@@ -85,19 +85,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return bool
- */
- public function db_select()
- {
- // Connection selects the database
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
* Database version number
*
* @return string
diff --git a/system/database/drivers/oci8/oci8_driver.php b/system/database/drivers/oci8/oci8_driver.php
index 3bc8c11..45b0198 100644
--- a/system/database/drivers/oci8/oci8_driver.php
+++ b/system/database/drivers/oci8/oci8_driver.php
@@ -186,19 +186,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return resource
- */
- public function db_select()
- {
- // Not in Oracle - schemas are actually usernames
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
* Database version number
*
* @return string
diff --git a/system/database/drivers/odbc/odbc_driver.php b/system/database/drivers/odbc/odbc_driver.php
index ad77311..ed901bd 100644
--- a/system/database/drivers/odbc/odbc_driver.php
+++ b/system/database/drivers/odbc/odbc_driver.php
@@ -95,19 +95,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return resource
- */
- public function db_select()
- {
- // Not needed for ODBC
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
* Execute the query
*
* @param string an SQL query
diff --git a/system/database/drivers/pdo/pdo_driver.php b/system/database/drivers/pdo/pdo_driver.php
index f336eb0..a9bed36 100644
--- a/system/database/drivers/pdo/pdo_driver.php
+++ b/system/database/drivers/pdo/pdo_driver.php
@@ -247,19 +247,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return resource
- */
- public function db_select()
- {
- // Not needed for PDO
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
* Database version number
*
* @return string
diff --git a/system/database/drivers/postgre/postgre_driver.php b/system/database/drivers/postgre/postgre_driver.php
index 3e2d05c..a033d74 100644
--- a/system/database/drivers/postgre/postgre_driver.php
+++ b/system/database/drivers/postgre/postgre_driver.php
@@ -162,19 +162,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return resource
- */
- public function db_select()
- {
- // Not needed for Postgre so we'll return TRUE
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
* Set client character set
*
* @param string
diff --git a/system/database/drivers/sqlite/sqlite_driver.php b/system/database/drivers/sqlite/sqlite_driver.php
index 102c79b..ef543c9 100644
--- a/system/database/drivers/sqlite/sqlite_driver.php
+++ b/system/database/drivers/sqlite/sqlite_driver.php
@@ -106,18 +106,6 @@
// --------------------------------------------------------------------
/**
- * Select the database
- *
- * @return resource
- */
- public function db_select()
- {
- return TRUE;
- }
-
- // --------------------------------------------------------------------
-
- /**
* Database version number
*
* @return string