Query Results
class CI_DB_result
Functions
result([$type = 'object'])
Parameter | Type | Description |
---|---|---|
$type | String |
The type of result to pull, either 'object' or 'array' |
Returns | Array of Objects/multidimensional array |
An array of Objects representing database rows or a multidimensional array of database rows |
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;
}
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()
Parameter | Type | Description |
---|---|---|
Returns | Multidimensional array |
An multidimensional array of database rows |
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 $row['body'];
}
row([$n = 0[, $type = 'object']])
Parameter | Type | Description |
---|---|---|
$n | Int |
The specific row to return |
$type | String |
The type of result to pull, either 'object' or 'array' |
Returns | Object/Array |
An object or array representing the 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);
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 = $query->previous_row();
row_array([$n = 0])
Parameter | Type | Description |
---|---|---|
$n | Int |
The specific row to return |
Returns | Array |
An array representing the row |
Identical to the above row()
function, except it returns an array:
$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);
Just like row()
, you can walk through your results using these variations:
$row = $query->first_row('array');
$row = $query->last_row('array');
$row = $query->next_row('array');
$row = $query->previous_row('array');
Result Helper Functions
num_rows()
Parameter | Type | Description |
---|---|---|
Returns | Int |
The number or rows returned by the query |
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();
num_fields()
Parameter | Type | Description |
---|---|---|
Returns | Int |
The number or fields returned by the query |
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();
free_result()
Parameter | Type | Description |
---|---|---|
Returns | Void |
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