Deprecate the 'mysql', 'sqlite', 'mssql' and 'pdo/dblib' drivers

The 'mysql' PHP extension is notorious for it's problems and is deprecated as of PHP 5.5.

The other ones are dropped from PHP 5.3.

2 files changed, 22 insertions, 0 deletions

diff --git a/user_guide_src/source/changelog.rst b/user_guide_src/source/changelog.rst
index 906c303a4..5b0187350 100644
--- a/user_guide_src/source/changelog.rst
+++ b/user_guide_src/source/changelog.rst
@@ -20,6 +20,7 @@ Release Date: Not Released
 
    -  PHP 5.1.6 is no longer supported. CodeIgniter now requires PHP 5.2.4.
    -  Changed filenaming convention (class file names now must be Ucfirst and everything else in lowercase).
+   -  Changed the default database driver to 'mysqli' (the old 'mysql' driver is DEPRECATED).
    -  ``$_SERVER['CI_ENV']`` can now be set to control the ``ENVIRONMENT`` constant.
    -  Added an optional backtrace to php-error template.
    -  Added Android to the list of user agents.
@@ -139,6 +140,7 @@ Release Date: Not Released
 
 -  Database
 
+   -  DEPRECATED the 'mysql', 'sqlite', 'mssql' and 'pdo/dblib' (also known as 'pdo/mssql' or 'pdo/sybase') drivers.
    -  Added **dsn** configuration setting for drivers that support DSN strings (PDO, PostgreSQL, Oracle, ODBC, CUBRID).
    -  Added **schema** configuration setting (defaults to *public*) for drivers that might need it (currently used by PostgreSQL and ODBC).
    -  Added subdrivers support (currently only used by PDO).
diff --git a/user_guide_src/source/installation/upgrade_300.rst b/user_guide_src/source/installation/upgrade_300.rst
index f0759a15e..ca7569b57 100644
--- a/user_guide_src/source/installation/upgrade_300.rst
+++ b/user_guide_src/source/installation/upgrade_300.rst
@@ -333,6 +333,26 @@ Smiley helper js_insert_smiley()
 :doc:`Smiley Helper <../helpers/smiley_helper>` function ``js_insert_smiley()`` has been deprecated
 since CodeIgniter 1.7.2 and is now removed. You'll need to switch to ``smiley_js()`` instead.
 
+Database drivers 'mysql', 'sqlite', 'mssql', 'pdo/dblib'
+========================================================
+
+The **mysql** driver utilizes the old 'mysql' PHP extension, known for its aging code base and
+many low-level problems. The extension is deprecated as of PHP 5.5 and CodeIgniter deprecates
+it in version 3.0, switching the default configured MySQL driver to **mysqli**.
+
+Please use either the 'mysqli' or 'pdo/mysql' drivers for MySQL. The old 'mysql' driver will be
+removed at some point in the future.
+
+The **sqlite**, **mssql** and **pdo/dblib** (also known as pdo/mssql or pdo/sybase) drivers
+all depend on PHP extensions that for different reasons no longer exist since PHP 5.3.
+
+Therefore we are now deprecating these drivers as we will have to remove them in one of the next
+CodeIgniter versions. You should use the more advanced, **sqlite3**, **sqlsrv** or **pdo/sqlsrv**
+drivers respectively.
+
+.. note:: These drivers are still available, but you're strongly encouraged to switch to other ones
+	sooner rather than later.
+
 Security helper do_hash()
 =========================