Once you have a query object built, either through a parameterized statement or through the builder, you must then execute()
the query and retrieve the results. Depending on the query type used, the results returned will vary.
DB::select will return a Database_Result object which you can then iterate over. This example shows how you can iterate through the Database_Result using a foreach.
$results
= DB::select()
->from(
'users'
)
->where(
'verified'
,
'='
, 0)
->execute();
foreach
(
$results
as
$user
) {
// Send reminder email to $user['email']
echo
$user
[
'email'
] .
" needs to verify his/her account\n"
;
}
as_object()
and as_assoc()
link to thisWhen iterating over a result set, the default type will be an associative array with the column names or aliases as the keys. As an option, before calling execute()
, you can specify to return the result rows as an object by using the as_object()
method. The as_object()
method takes one parameter, the name of the class of your choice, but will default to true which uses the stdClass
. Here is the example again using stdClass
.
$results
= DB::select()
->from(
'users'
)
->where(
'verified'
,
'='
, 0)
->as_object()
->execute();
foreach
(
$results
as
$user
) {
// Send reminder email to $user->email
echo
$user
->email .
" needs to verify his/her account\n"
;
}
The method as_assoc()
will remove the object name and return the results set back to an associative array. Since this is the default, this method is seldom required.
as_array()
link to thisSometimes you will require the results as a pure array rather than as an object. The Database_Result
method as_array()
will return an array of all rows.
$results
= DB::select(
'id'
,
'email'
)
->from(
'users'
)
->execute();
$users
=
$results
->as_array();
foreach
(
$users
as
$user
) {
echo
'User ID: '
. $ user[
'id'
];
echo
'User Email: '
.
$user
[
'email'
];
}
It also accepts two parameters that can be very helpful: $key
and $value
. When passing a value to $key
you will index the resulting array by the column specified.
$results
= DB::select(
'id'
,
'email'
)
->from(
'users'
)
->execute();
$users
=
$results
->as_array(
'id'
);
foreach
(
$users
as
$id
=>
$user
) {
echo
'User ID: '
.
$id
;
echo
'User Email: '
.
$user
[
'email'
];
}
The second parameter, $value
, will reference the column specified and return that value rather than the whole row. This is particularly useful when making <select>
dropdowns.
$results
= DB::select(
'id'
,
'name'
)
->from(
'users'
)
->execute();
$users
=
$results
->as_array(
'id'
,
'name'
);
// Show a dropdown with all users in it.
echo
Form::select(
'author'
,
$users
);
To return a non-associative array, leave $key
as null and just pass a $value
.
$results
= DB::select(
'email'
)
->from(
'users'
)
->execute();
$users
=
$results
->as_array(null,
'email'
);
foreach
(
$users
as
) {
echo
'User Email: '
.
;
}
get()
link to thisSometime you only want a single value from a query. The get()
method returns the value of the named column from the current row. The second parameter, $default
, is used to supply a default value when the result is null.
$totalUsers
= DB::select([DB::expr(
'COUNT(`username`)'
),
'total_users'
])
->from(
'users'
)
->execute()
->get(
'total_users'
, 0);
cached()
link to thisThe mysql database driver returns a Database_Result
that works with a MySQL Resource data type. Since this resource lives outside of PHP environment, it can't be serialized which means it also can't be cached. To get around this the Database_Result
object has the cached()
method that returns a Database_Result_Cached
object of the result set. The Database_Result_Cached
can be serialized and cached, but can take up more memory.
NOTE: Currently, the PDO diver always returns a class of Database_Result_Cached
, so cached()
just returns itself.
The cached()
function doesn't actually do any caching, it simply returns the result in a way that can be serialized and cached. You will need to use the Cache Module or some other caching method.
count()
link to thisThe Database_Result
object implements the Countable
Interface. The method count()
returns the total row count in the result set.
NOTE: This is the count of the current result set, not a count of how many records are in the database. This is important to point out especially when using limit()
and offset()
in your query.
For a complete list of methods available when working with a result set see Database_Result.
DB::insert returns an array of two values: the last insert id and the number of affected rows.
$insert
= DB::insert(
'tools'
)
->columns([
'name'
,
'model'
,
'description'
])
->values([
'Skil 3400'
,
'3400'
,
'Powerful 15 amp motor; weighs just 54-pounds'
]);
list(
$insertId
,
$affectedRows
) =
$insert
->execute();
DB::update and DB::delete both return the number of affected rows as an integer.
$rowsDeleted
= DB::
delete
(
'tools'
)
->where(
'model'
,
'like'
,
'3400'
)
->execute();