From 8ede1a2ecbb62577afd32996956c5feaf7ddf9b6 Mon Sep 17 00:00:00 2001 From: Derek Jones Date: Wed, 5 Oct 2011 13:34:52 -0500 Subject: replacing the old HTML user guide with a Sphinx-managed user guide --- user_guide/database/results.html | 259 --------------------------------------- 1 file changed, 259 deletions(-) delete mode 100644 user_guide/database/results.html (limited to 'user_guide/database/results.html') diff --git a/user_guide/database/results.html b/user_guide/database/results.html deleted file mode 100644 index a47e335cb..000000000 --- a/user_guide/database/results.html +++ /dev/null @@ -1,259 +0,0 @@ - - - - - -Generating Query Results : CodeIgniter User Guide - - - - - - - - - - - - - - - - - - - - - -
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CodeIgniter User Guide Version 2.0.3

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Generating Query Results

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There are several ways to generate query results:

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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

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$query->num_rows()

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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()

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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()

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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 - - - - - - -
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