Query Interface
The query interface provides different ways to retrieve data from the database. Using the query interface you can find records using a variety of methods and conditions; specify the order, fields, grouping, limit, or the tables to join; use dynamic or scoped filters; check the existence or particular records; perform various calculations.
Queries often starts from a model, in the following examples the $model
variable is a reference
to a model managing nodes.
Retrieving records from the database
To retrieve objects and values from the database several finder methods are provided. Each of these methods defines the fragments of the database query. Complex queries can be created without having to write any raw SQL.
The methods are:
- where
- select
- group
- having
- order
- limit
- offset
- join
All of the above methods return a Query instance, allowing you to chain them.
Records can be retrieved in various ways, especially using the all
, one
, pairs
or rc
magic properties. The find()
method—used to retrieve a single record or a set of records—is the
most simple of them.
Retrieving a single record
Retrieving a single record using its primary key is really simple. You can either use the find()
method of the model, or use the model as an array.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$article = $model->find(10);
# or
$article = $model[10];
Retrieving a set of records
Retrieving a set or records using their primary key is really simple too:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$articles = $model->find([ 10, 32, 89 ]);
# or
$articles = $model->find(10, 32, 89);
The RecordNotFound exception is thrown when a record could not be found. Its records
property
can be used to know which records could be found and which could not.
Note: The records of the set are returned in the same order they are requested, this also applies
to the records
property of the RecordNotFound exception.
Records caching
Records retrieved using find()
are cached, they are reused by subsequent calls. This also
applies to the array notation.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$article = $model[12]; // '12' retrieved from database
$articles = $model->find(11, 12, 13); // '11' and '13' retrieved from database, '12' is reused.
Conditions
The where()
method specifies the conditions used to filter the records. It represents
the WHERE
-part of the SQL statement. Conditions can either be specified as a string, as a
list of arguments or as an array.
Conditions specified as a string
Adding a condition to a query can be as simple as $model->where('is_online = 1');
. This
would return all the records where the is_online
field equals "1".
Warning: Building you own conditions as string can leave you vulnerable to SQL injection
exploits. For instance, $model->where('is_online = ' . $_GET['online']);
is not safe. Always
use placeholders when you can't trust the source of your inputs:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where('is_online = ?', $_GET['online']);
Of course you can use multiple conditions:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where('is_online = ? AND is_home_excluded = ?', $_GET['online'], false);
and()
is alias to where()
and should be preferred when linking adding conditions:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where('is_online = ?', $_GET['online'])->and('is_home_excluded = ?', false);
Conditions specified as an array (or list of arguments)
Conditions can also be specified as arrays:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where([ 'is_online' => $_GET['online'], 'is_home_excluded' => false ]);
Subset conditions
Records belonging to a subset can be retrieved using an array as condition value:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where([ 'orders_count' => [ 1,3,5 ] ]);
This generates something like: ... WHERE (orders_count IN (1,3,5))
.
Modifiers
When conditions are specified as an array it is possible to modify the comparing function. Prefixing a field name with an exclamation mark uses the not equal operator.
The following example demonstrates how to search for records where the order_count
field is
different than "2":
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where([ '!order_count' => 2 ]);
… WHERE `order_count` != 2
This also works with subsets:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where([ '!order_count' => [ 1,3,5 ] ]);
… WHERE `order_count` NOT IN(1, 3, 5)
Dynamic filters
Conditions can also be specified as methods, prefixed by filter_by_
and separated by _and_
:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->filter_by_slug('creer-nuage-mots-cle');
$model->filter_by_is_online_and_uid(true, 3);
Is equivalent to:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where([ 'slug' => 'creer-nuage-mots-cle' ]);
$model->where([ 'is_online' => true, 'uid' => 3 ]);
Scopes
Scopes can be viewed as model defined filters. Models can define their own filters,
inherit filters from their parent class and override them. For instance, this is how a
similar_site
, similar_language
and visible
scopes could be defined:
<?php
namespace Website\Nodes;
use ICanBoogie\ActiveRecord\Query;
class Model extends \ICanBoogie\ActiveRecord\Model
{
// …
protected function scope_similar_site(Query $query, $site_id = null)
{
return $query->and('site_id = 0 OR site_id = ?', $site_id !== null ? $site_id : $this->current_site_id);
}
protected function scope_similar_language(Query $query, $language = null)
{
return $query->and('language = "" OR language = ?', $language !== null ? $language : $this->current_language);
}
protected function scope_visible(Query $query, $visible = true)
{
return $query->similar_site->similar_language->filter_by_is_online($visible);
}
// …
}
Now you can easily retrieve the first ten records that are visible on your website:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->visible->limit(10);
Or retrieve the first ten French records:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->similar_language('fr')->limit(10);
Ordering
The order()
method retrieves records in a specific order.
The following example demonstrates how to get records in the ascending order of their creation date:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->order('created');
A direction can be specified:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->order('created ASC');
# or
$model->order('created DESC');
Multiple fields can be used while ordering:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->order('created DESC, title');
Records can also be ordered by field:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where([ 'nid' => [ 1, 2, 3 ] ])->order('nid', [ 2, 3, 1 ]);
# or
$model->where([ 'nid' => [ 1, 2, 3 ] ])->order('nid', 2, 3, 1);
Grouping data
The group()
method specifies the GROUP BY
clause.
The following example demonstrates how to retrieve the first record of records grouped by day:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->group('date(created)')->order('created');
Filtering groups
The having()
method specifies the HAVING
clause, which specifies the conditions of the
GROUP BY
clause.
The following example demonstrates how to retrieve the first record created by day for the past month:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->group('date(created)')->having('created > ?', new DateTime('-1 month'))->order('created');
Limit and offset
The limit()
method limits the number of records to retrieve.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->limit(10); // retrieves the first 10 records
With two arguments, an offset can be specified:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->limit(5, 10); // retrieves records from the 6th to the 16th
The offset can also be defined using the offset()
method:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->offset(5); // retrieves records from the 6th to the last
$model->limit(10)->offset(5);
Selecting specific fields
By default all fields are selected (SELECT *
) and records are instances of the ActiveRecord
class defined by the model. The select()
method selects only a subset of fields from
the result set, in which case each row of the result set is returned as an array, unless a fetch
mode is defined.
The following example demonstrates how to get the identifier, creation date and title of records:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->select('nid, created, title');
Because the SELECT
string is used as is to build the query, complex SQL statements can be
used:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->select('nid, created, CONCAT_WS(":", title, language)');
Joining tables
The join()
method specifies the JOIN
clause. A raw string or a model identifier
can be used to specify the join. The method can be used multiple times to create multiple joints.
Joining tables using a subquery
A Query instance can be joined as a subquery. The following options are available:
mode
: Specifies the join mode. Default:INNER
.as
: Alias for the subquery. Default: The alias of the model associated with the query.on
: The column used for the conditional expression. Depending on the columns available, the method tries to determine the best solution betweenON
andUSING
.
The following example demonstrates how to fetch users and order them by the number
of online article they published since last year. We use the join mode LEFT
so that users
that did not publish articles are fetched as well.
<?php
/* @var $models \ICanBoogie\ActiveRecord\ModelCollection */
$online_article_count = $models['articles']
->select('user_id, COUNT(node_id) AS online_article_count')
->filter_by_type_and_created_at('articles', new DateTime('-1 year'))
->online
->group('user_id');
$users = $models['users']
->join($online_article_count, [ 'on' => 'user_id', 'mode' => 'LEFT' ])
->order('online_article_count DESC');
Joining tables using a model
A join can be specified using a model or a model identifier, in which case the relationship between that model and the model associated with the query is used to create the join. The following options are available:
mode
: Specifies the join mode. Default:INNER
.as
: Alias for the joining model. Default: The alias of the joining model.
The column character ":" is used to distinguish a model identifier from a raw fragment.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
/* @var $contents_model \ICanBoogie\ActiveRecord\Model */
$model->join($contents_model);
# or
$model->join(':contents');
$model->join(':contents', [ 'mode' => 'LEFT', 'as' => 'cnt' ]);
Note: If a model identifier is provided, the model collection associated with the query's model is used to obtain the model.
Joining tables using a raw string
Finally, a join can be specified using a raw string, which will be included as is in the final SQL statement.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->join('INNER JOIN `contents` USING(`nid`)');
Retrieving data
There are many ways to retrieve data. We have already seen the find()
method, which can be used
to retrieve records using their identifier. The following methods or magic properties work with
conditions.
Retrieving data by iteration
Instances of Query are traversable, it's the easiest way the retrieve the rows of a result set:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
foreach ($model->where('is_online = 1') as $node)
{
// …
}
Retrieving the complete result set
The magic property all
retrieves the complete result set as an array:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$array = $model->all;
$array = $model->visible->order('created DESC')->all;
The all()
method retrieves the complete result set using a specific fetch mode:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$array = $model->all(\PDO::FETCH_ASSOC);
$array = $model->visible->order('created DESC')->all(\PDO::FETCH_ASSOC);
Retrieving a single record
The one
magic property retrieves a single record:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$record = $model->one;
$record = $model->visible->order('created DESC')->one;
The one()
method retrieves a single record using a specific fetch mode:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$record = $model->one(\PDO::FETCH_ASSOC);
$record = $model->visible->order('created DESC')->one(\PDO::FETCH_ASSOC);
Note: The number of records to retrieve is automatically limited to 1.
Retrieving key/value pairs
The pairs
magic property retrieves key/value pairs when selecting two columns, the first column
is the key and the second its value.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->select('nid, title')->pairs;
Results are similar to the following example:
array
34 => string 'Créer un nuage de mots-clé' (length=28)
57 => string 'Générer à la volée des miniatures avec mise en cache' (length=56)
307 => string 'Mes premiers pas de développeur sous Ubuntu 10.04 (Lucid Lynx)' (length=63)
...
Retrieving the first column of the first row
The rc
magic property retrieves the first column of the first row.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$title = $model->select('title')->rc;
Note: The number of records to retrieve is automatically limited to 1.
Defining the fetch mode
The fetch mode is usually selected by the query interface but the mode
can be used to specify
it.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->select('nid, title')->mode(\PDO::FETCH_NUM);
The mode()
method accepts the same arguments as the
PDOStatement::setFetchMode method.
As we have seen in previous examples, the fetch mode can also be specified when fetching data
with the all()
and one()
methods.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$array = $model->order('created DESC')->all(\PDO::FETCH_ASSOC);
$record = $model->order('created DESC')->one(\PDO::FETCH_ASSOC);
Checking the existence of records
The exists()
method checks the existence of a record, it queries the database just like find()
but returns true
when a record is found and false
otherwise.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->exists(1);
The method accepts multiple identifiers in which case it returns true
when all the
records exist, false
when all the record don't exist, and an array otherwise.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->exists(1, 2, 999);
# or
$model->exists([ 1, 2, 999 ]);
The method would return the following result if records "1" and "2" exist but not record "999".
array
1 => boolean true
2 => boolean true
999 => boolean false
The exists
magic property is true
if at least one record matching the specified conditions
exists, false
otherwise.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->filter_by_author('Madonna')->exists;
The exists
magic property of the model is true
if the modal has at least one record, false
otherwise.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->exists;
Counting
The count
magic property is the number of records in a model or matching a query.
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->count;
Or on a query:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->filter_by_firstname('Ryan')->count;
Of course, all query methods can be combined:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->filter_by_firstname('Ryan')->join(':content')->where('YEAR(date) = 2011')->count;
The count()
method returns an array with the number of recond for each value of a field:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->count('is_online');
array
0 => string '35' (length=2)
1 => string '145' (length=3)
In this example, there are 35 record online and 145 offline.
Calculations
The average()
, minimum()
, maximum()
and sum()
methods are respectively used, for a column,
to compute its average value, its minimum value, its maximum value and its sum.
All calculation methods work directly on the model:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->average('price');
And on a query:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->filter_by_category('Toys')->average('price');
Of course, all query methods can be combined:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->filter_by_category('Toys')->join(':content')->where('YEAR(date) = 2011')->average('price');
Some useful properties
The following properties might be helpful, especially when you are using the Query interface to create a query string to be used in the subquery of another query:
conditions
: The conditions rendered as a string.conditions_args
: The arguments to the conditions.model
: The model associated with the query.
Using a query as a subquery
The following example demonstrates how a query on some taxonomy models can be used as a subquery to obtain only the online articles in a "music" category:
<?php
/* @var $models \ICanBoogie\ActiveRecord\ModelCollection */
$taxonomy_query = $models['taxonomy.terms/nodes']
->join(':taxonomy.vocabulary')
->join(':taxonomy_vocabulary/scopes')
->where([
'termslug' => "music",
'vocabularyslug' => "category",
'constructor' => "articles"
])
->select('nid');
$articles = $models['articles']
->filter_by_is_online(true)
->and("nid IN ($taxonomy_query)", $taxonomy_query->conditions_args)
->all;
# or
$articles = $models['articles']
->filter_by_is_online_and_nid(true, $taxonomy_query)
->all;
Deleting the records matching a query
The records matching a query can be deleted using the delete()
method:
<?php
/* @var $models \ICanBoogie\ActiveRecord\ModelCollection */
$models['nodes']
->filter_by_is_deleted_and_uid(true, 123)
->limit(10)
->delete();
You might need to join tables to decide which record to delete, in which case you might want to define in which tables the records should be deleted. The following example demonstrates how to delete the nodes and comments of nodes belonging to user 123 and marked as deleted:
<?php
/* @var $models \ICanBoogie\ActiveRecord\ModelCollection */
$models['comments']
->filter_by_is_deleted_and_uid(true, 123)
->join(':nodes')
->delete('comments, nodes');
When using join()
the table associated with the query is used by default. The following
example demonstrates how to delete nodes that lack content:
<?php
/* @var $models \ICanBoogie\ActiveRecord\ModelCollection */
$models['nodes']
->join(':contents', [ 'mode' => 'LEFT' ])
->where('content.nid IS NULL')
->delete();
Query interface summary
Retrieving records:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$record = $model[10];
# or
$record = $model->find(10);
$records = $model->find(10, 15, 19);
# or
$records = $model->find([ 10, 15, 19 ]);
Conditions:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->where('is_online = ?', true);
$model->where([ 'is_online' => true, 'is_home_excluded' => false ]);
$model->where('site_id = 0 OR site_id = ?', 1)->and('language = "" OR language = ?', "fr");
# Sets
$model->where([ 'order_count' => [ 1, 2, 3 ] ]);
$model->where([ '!order_count' => [ 1, 2, 3 ] ]); # NOT
# Dynamic filters
$model->filter_by_nid(1);
$model->filter_by_site_id_and_language(1, 'fr');
# Scopes
$model->visible;
$model->own->visible->ordered;
Grouping and ordering:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->group('date(created)')->order('created');
$model->group('date(created)')->having('created > ?', new DateTime('-1 month'))->order('created');
Limits and offsets:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->limit(10); // first 10 records
$model->limit(5, 10); // 6th to the 16th records
$model->offset(5); // from the 6th to the last
$model->offset(5)->limit(10);
Fields selection:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->select('nid, created, title');
$model->select('nid, created, CONCAT_WS(":", title, language)');
Joins:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->join($subquery, [ 'on' => 'nid' ]);
$model->join(':contents');
$model->join('INNER JOIN contents USING(nid)');
Retrieving data:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->all;
$model->order('created DESC')->all(PDO::FETCH_ASSOC);
$model->order('created DESC')->mode(PDO::FETCH_ASSOC)->all;
$model->order('created DESC')->one;
$model->select('nid, title')->pairs;
$model->select('title')->rc;
Testing object existence:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->exists;
$model->exists(1, 2, 3);
$model->exists([ 1, 2, 3 ]);
$model->where('author = ?', 'madonna')->exists;
Calculations:
<?php
/* @var $model \ICanBoogie\ActiveRecord\Model */
$model->count;
$model->count('is_online'); // count is_online = 0 and is_online = 1
$model->filter_by_is_online(true)->count; // count is_online = 1
$model->average('score');
$model->minimum('age');
$model->maximum('age');
$model->sum('comments_count');