Merged with develop and updated to new changelog.

1 files changed, 114 insertions, 0 deletions

diff --git a/user_guide_src/source/database/queries.rst b/user_guide_src/source/database/queries.rst
new file mode 100644
index 000000000..971d5d61d
--- /dev/null
+++ b/user_guide_src/source/database/queries.rst
@@ -0,0 +1,114 @@
+#######
+Queries
+#######
+
+$this->db->query();
+===================
+
+To submit a query, use the following function::
+
+	$this->db->query('YOUR QUERY HERE');
+
+The query() function returns a database result **object** when "read"
+type queries are run, which you can use to :doc:`show your
+results <results>`. When "write" type queries are run it simply
+returns TRUE or FALSE depending on success or failure. When retrieving
+data you will typically assign the query to your own variable, like
+this::
+
+	$query = $this->db->query('YOUR QUERY HERE');
+
+$this->db->simple_query();
+===========================
+
+This is a simplified version of the $this->db->query() function. It ONLY
+returns TRUE/FALSE on success or failure. It DOES NOT return a database
+result set, nor does it set the query timer, or compile bind data, or
+store your query for debugging. It simply lets you submit a query. Most
+users will rarely use this function.
+
+***************************************
+Working with Database prefixes manually
+***************************************
+
+If you have configured a database prefix and would like to prepend it to
+a table name for use in a native SQL query for example, then you can use
+the following::
+
+	$this->db->dbprefix('tablename'); // outputs prefix_tablename
+
+
+If for any reason you would like to change the prefix programatically
+without needing to create a new connection, you can use this method::
+
+	$this->db->set_dbprefix('newprefix');
+	$this->db->dbprefix('tablename'); // outputs newprefix_tablename
+
+
+**********************
+Protecting identifiers
+**********************
+
+In many databases it is advisable to protect table and field names - for
+example with backticks in MySQL. **Active Record queries are
+automatically protected**, however if you need to manually protect an
+identifier you can use::
+
+	$this->db->protect_identifiers('table_name');
+
+
+This function will also add a table prefix to your table, assuming you
+have a prefix specified in your database config file. To enable the
+prefixing set TRUE (boolen) via the second parameter::
+
+	$this->db->protect_identifiers('table_name', TRUE);
+
+
+****************
+Escaping Queries
+****************
+
+It's a very good security practice to escape your data before submitting
+it into your database. CodeIgniter has three methods that help you do
+this:
+
+#. **$this->db->escape()** This function determines the data type so
+   that it can escape only string data. It also automatically adds
+   single quotes around the data so you don't have to:
+   ::
+
+	$sql = "INSERT INTO table (title) VALUES(".$this->db->escape($title).")";
+
+#. **$this->db->escape_str()** This function escapes the data passed to
+   it, regardless of type. Most of the time you'll use the above
+   function rather than this one. Use the function like this:
+   ::
+
+	$sql = "INSERT INTO table (title) VALUES('".$this->db->escape_str($title)."')";
+
+#. **$this->db->escape_like_str()** This method should be used when
+   strings are to be used in LIKE conditions so that LIKE wildcards
+   ('%', '\_') in the string are also properly escaped.
+
+::
+
+	$search = '20% raise'; $sql = "SELECT id FROM table WHERE column LIKE '%".$this->db->escape_like_str($search)."%'";
+
+
+**************
+Query Bindings
+**************
+
+Bindings enable you to simplify your query syntax by letting the system
+put the queries together for you. Consider the following example::
+
+	$sql = "SELECT * FROM some_table WHERE id = ? AND status = ? AND author = ?";
+	$this->db->query($sql, array(3, 'live', 'Rick'));
+
+The question marks in the query are automatically replaced with the
+values in the array in the second parameter of the query function.
+
+The secondary benefit of using binds is that the values are
+automatically escaped, producing safer queries. You don't have to
+remember to manually escape data; the engine does it automatically for
+you.