Merge branch 'develop' of github.com:EllisLab/CodeIgniter into develop

1 files changed, 124 insertions, 0 deletions

diff --git a/user_guide_src/source/database/results.rst b/user_guide_src/source/database/results.rst
new file mode 100644
index 000000000..a85b89bef
--- /dev/null
+++ b/user_guide_src/source/database/results.rst
@@ -0,0 +1,124 @@
+########################
+Generating Query Results
+########################
+
+There are several ways to generate query results:
+
+result()
+========
+
+This function returns the query result as an array of **objects**, or
+**an empty array** on failure. Typically you'll use this in a foreach
+loop, like this::
+
+	     $query = $this->db->query("YOUR QUERY");          foreach ($query->result() as $row)     {        echo $row->title;        echo $row->name;        echo $row->body;     }
+
+The above function is an alias of result_object().
+
+If you run queries that might **not** produce a result, you are
+encouraged to test the result first::
+
+	     $query = $this->db->query("YOUR QUERY");          if ($query->num_rows() > 0)     {        foreach ($query->result() as $row)        {           echo $row->title;           echo $row->name;           echo $row->body;        }     }     
+
+You can also pass a string to result() which represents a class to
+instantiate for each result object (note: this class must be loaded)
+
+::
+
+	$query = $this->db->query("SELECT * FROM users;");
+
+	foreach ($query->result('User') as $user)
+	{
+	   echo $user->name; // call attributes
+	   echo $user->reverse_name(); // or methods defined on the 'User' class
+	}
+
+result_array()
+===============
+
+This function returns the query result as a pure array, or an empty
+array when no result is produced. Typically you'll use this in a foreach
+loop, like this::
+
+	     $query = $this->db->query("YOUR QUERY");          foreach ($query->result_array() as $row)     {        echo $row['title'];        echo $row['name'];        echo $row['body'];     }
+
+row()
+=====
+
+This function returns a single result row. If your query has more than
+one row, it returns only the first row. The result is returned as an
+**object**. Here's a usage example::
+
+	     $query = $this->db->query("YOUR QUERY");          if ($query->num_rows() > 0)     {        $row = $query->row();             echo $row->title;        echo $row->name;        echo $row->body;     }     
+
+If you want a specific row returned you can submit the row number as a
+digit in the first parameter::
+
+	$row = $query->row(5);
+
+You can also add a second String parameter, which is the name of a class
+to instantiate the row with::
+
+	     $query = $this->db->query("SELECT * FROM users LIMIT 1;");          $query->row(0, 'User')     echo $row->name; // call attributes     echo $row->reverse_name(); // or methods defined on the 'User' class     
+
+row_array()
+============
+
+Identical to the above row() function, except it returns an array.
+Example::
+
+	     $query = $this->db->query("YOUR QUERY");          if ($query->num_rows() > 0)     {        $row = $query->row_array();             echo $row['title'];        echo $row['name'];        echo $row['body'];     }     
+
+If you want a specific row returned you can submit the row number as a
+digit in the first parameter::
+
+	$row = $query->row_array(5);
+
+In addition, you can walk forward/backwards/first/last through your
+results using these variations:
+
+**$row = $query->first_row()**
+ **$row = $query->last_row()**
+ **$row = $query->next_row()**
+ **$row = $query->previous_row()**
+
+By default they return an object unless you put the word "array" in the
+parameter:
+
+**$row = $query->first_row('array')**
+ **$row = $query->last_row('array')**
+ **$row = $query->next_row('array')**
+ **$row = $query->previous_row('array')**
+
+***********************
+Result Helper Functions
+***********************
+
+$query->num_rows()
+===================
+
+The number of rows returned by the query. Note: In this example, $query
+is the variable that the query result object is assigned to::
+
+	$query = $this->db->query('SELECT * FROM my_table'); echo $query->num_rows();
+
+$query->num_fields()
+=====================
+
+The number of FIELDS (columns) returned by the query. Make sure to call
+the function using your query result object::
+
+	$query = $this->db->query('SELECT * FROM my_table'); echo $query->num_fields();
+
+$query->free_result()
+======================
+
+It frees the memory associated with the result and deletes the result
+resource ID. Normally PHP frees its memory automatically at the end of
+script execution. However, if you are running a lot of queries in a
+particular script you might want to free the result after each query
+result has been generated in order to cut down on memory consumptions.
+Example::
+
+	$query = $this->db->query('SELECT title FROM my_table'); foreach ($query->result() as $row) {    echo $row->title; } $query->free_result();  // The $query result object will no longer be available  $query2 = $this->db->query('SELECT name FROM some_table'); $row = $query2->row(); echo $row->name; $query2->free_result();  // The $query2 result object will no longer be available
+