Introduction
Laravel's database query builder provides a convenient, fluent interface to creating and running database queries. It can be used to perform most database operations in your application and works on all supported database systems.
The Laravel query builder uses PDO parameter binding to protect your application against SQL injection attacks. There is no need to clean strings being passed as bindings.
Retrieving Results
Retrieving All Rows From A Table
You may use the table
method on the DB
facade to begin a query. The table
method returns a fluent
query builder instance for the given table, allowing you to chain more
constraints onto the query and then finally get the results using the
get
method:
<?php
namespace App\Http\Controllers;
use Illuminate\Support\Facades\DB;
use App\Http\Controllers\Controller;
class UserController extends Controller
{
/**
* Show a list of all of the application's users.
*
* @return Response
*/
public function index()
{
$users = DB::table('users')->get();
return view('user.index', ['users' => $users]);
}
}
The get
method returns an
Illuminate\Support\Collection
containing the results where
each result is an instance of the PHP StdClass
object. You
may access each column's value by accessing the column as a property of
the object:
foreach ($users as $user) {
echo $user->name;
}
Retrieving A Single Row / Column From A Table
If you just need to retrieve a single row from the database table,
you may use the first
method. This method will return a
single StdClass
object:
$user = DB::table('users')->where('name', 'John')->first();
echo $user->name;
If you don't even need an entire row, you may extract a single value
from a record using the value
method. This method will
return the value of the column directly:
$email = DB::table('users')->where('name', 'John')->value('email');
Retrieving A List Of Column Values
If you would like to retrieve a Collection containing the values of a
single column, you may use the pluck
method. In this
example, we'll retrieve a Collection of role titles:
$titles = DB::table('roles')->pluck('title');
foreach ($titles as $title) {
echo $title;
}
You may also specify a custom key column for the returned Collection:
$roles = DB::table('roles')->pluck('title', 'name');
foreach ($roles as $name => $title) {
echo $title;
}
Chunking Results
If you need to work with thousands of database records, consider
using the chunk
method. This method retrieves a small chunk
of the results at a time and feeds each chunk into a
Closure
for processing. This method is very useful for
writing Artisan commands that process
thousands of records. For example, let's work with the entire
users
table in chunks of 100 records at a time:
DB::table('users')->orderBy('id')->chunk(100, function ($users) {
foreach ($users as $user) {
//
}
});
You may stop further chunks from being processed by returning
false
from the Closure
:
DB::table('users')->orderBy('id')->chunk(100, function ($users) {
// Process the records...
return false;
});
Aggregates
The query builder also provides a variety of aggregate methods such
as count
, max
, min
,
avg
, and sum
. You may call any of these
methods after constructing your query:
$users = DB::table('users')->count();
$price = DB::table('orders')->max('price');
Of course, you may combine these methods with other clauses:
$price = DB::table('orders')
->where('finalized', 1)
->avg('price');
Selects
Specifying A Select Clause
Of course, you may not always want to select all columns from a
database table. Using the select
method, you can specify a
custom select
clause for the query:
$users = DB::table('users')->select('name', 'email as user_email')->get();
The distinct
method allows you to force the query to
return distinct results:
$users = DB::table('users')->distinct()->get();
If you already have a query builder instance and you wish to add a
column to its existing select clause, you may use the
addSelect
method:
$query = DB::table('users')->select('name');
$users = $query->addSelect('age')->get();
Raw Expressions
Sometimes you may need to use a raw expression in a query. To create
a raw expression, you may use the DB::raw
method:
$users = DB::table('users')
->select(DB::raw('count(*) as user_count, status'))
->where('status', '<>', 1)
->groupBy('status')
->get();
Note: Raw statements will be injected into the query as strings, so you should be extremely careful to not create SQL injection vulnerabilities.
Raw Methods
Instead of using DB::raw
, you may also use the following
methods to insert a raw expression into various parts of your query.
selectRaw
The selectRaw
method can be used in place of
select(DB::raw(...))
. This method accepts an optional array
of bindings as its second argument:
$orders = DB::table('orders')
->selectRaw('price * ? as price_with_tax', [1.0825])
->get();
whereRaw / orWhereRaw
The whereRaw
and orWhereRaw
methods can be
used to inject a raw where
clause into your query. These
methods accept an optional array of bindings as their second
argument:
$orders = DB::table('orders')
->whereRaw('price > IF(state = "TX", ?, 100)', [200])
->get();
havingRaw / orHavingRaw
The havingRaw
and orHavingRaw
methods may
be used to set a raw string as the value of the having
clause:
$orders = DB::table('orders')
->select('department', DB::raw('SUM(price) as total_sales'))
->groupBy('department')
->havingRaw('SUM(price) > 2500')
->get();
orderByRaw
The orderByRaw
method may be used to set a raw string as
the value of the order by
clause:
$orders = DB::table('orders')
->orderByRaw('updated_at - created_at DESC')
->get();
Joins
Inner Join Clause
The query builder may also be used to write join statements. To
perform a basic "inner join", you may use the join
method
on a query builder instance. The first argument passed to the
join
method is the name of the table you need to join to,
while the remaining arguments specify the column constraints for the
join. Of course, as you can see, you can join to multiple tables in a
single query:
$users = DB::table('users')
->join('contacts', 'users.id', '=', 'contacts.user_id')
->join('orders', 'users.id', '=', 'orders.user_id')
->select('users.*', 'contacts.phone', 'orders.price')
->get();
Left Join Clause
If you would like to perform a "left join" instead of an "inner
join", use the leftJoin
method. The leftJoin
method has the same signature as the join
method:
$users = DB::table('users')
->leftJoin('posts', 'users.id', '=', 'posts.user_id')
->get();
Cross Join Clause
To perform a "cross join" use the crossJoin
method with
the name of the table you wish to cross join to. Cross joins generate a
cartesian product between the first table and the joined table:
$users = DB::table('sizes')
->crossJoin('colours')
->get();
Advanced Join Clauses
You may also specify more advanced join clauses. To get started, pass
a Closure
as the second argument into the join
method. The Closure
will receive a JoinClause
object which allows you to specify constraints on the join
clause:
DB::table('users')
->join('contacts', function ($join) {
$join->on('users.id', '=', 'contacts.user_id')->orOn(...);
})
->get();
If you would like to use a "where" style clause on your joins, you
may use the where
and orWhere
methods on a
join. Instead of comparing two columns, these methods will compare the
column against a value:
DB::table('users')
->join('contacts', function ($join) {
$join->on('users.id', '=', 'contacts.user_id')
->where('contacts.user_id', '>', 5);
})
->get();
Unions
The query builder also provides a quick way to "union" two queries
together. For example, you may create an initial query and use the
union
method to union it with a second query:
$first = DB::table('users')
->whereNull('first_name');
$users = DB::table('users')
->whereNull('last_name')
->union($first)
->get();
Tip!! The
unionAll
method is also available and has the same method signature asunion
.
Where Clauses
Simple Where Clauses
You may use the where
method on a query builder instance
to add where
clauses to the query. The most basic call to
where
requires three arguments. The first argument is the
name of the column. The second argument is an operator, which can be any
of the database's supported operators. Finally, the third argument is
the value to evaluate against the column.
For example, here is a query that verifies the value of the "votes" column is equal to 100:
$users = DB::table('users')->where('votes', '=', 100)->get();
For convenience, if you want to verify that a column is equal to a
given value, you may pass the value directly as the second argument to
the where
method:
$users = DB::table('users')->where('votes', 100)->get();
Of course, you may use a variety of other operators when writing a
where
clause:
$users = DB::table('users')
->where('votes', '>=', 100)
->get();
$users = DB::table('users')
->where('votes', '<>', 100)
->get();
$users = DB::table('users')
->where('name', 'like', 'T%')
->get();
You may also pass an array of conditions to the where
function:
$users = DB::table('users')->where([
['status', '=', '1'],
['subscribed', '<>', '1'],
])->get();
Or Statements
You may chain where constraints together as well as add
or
clauses to the query. The orWhere
method
accepts the same arguments as the where
method:
$users = DB::table('users')
->where('votes', '>', 100)
->orWhere('name', 'John')
->get();
Additional Where Clauses
whereBetween
The whereBetween
method verifies that a column's value
is between two values:
$users = DB::table('users')
->whereBetween('votes', [1, 100])->get();
whereNotBetween
The whereNotBetween
method verifies that a column's
value lies outside of two values:
$users = DB::table('users')
->whereNotBetween('votes', [1, 100])
->get();
whereIn / whereNotIn
The whereIn
method verifies that a given column's value
is contained within the given array:
$users = DB::table('users')
->whereIn('id', [1, 2, 3])
->get();
The whereNotIn
method verifies that the given column's
value is not contained in the given array:
$users = DB::table('users')
->whereNotIn('id', [1, 2, 3])
->get();
whereNull / whereNotNull
The whereNull
method verifies that the value of the
given column is NULL
:
$users = DB::table('users')
->whereNull('updated_at')
->get();
The whereNotNull
method verifies that the column's value
is not NULL
:
$users = DB::table('users')
->whereNotNull('updated_at')
->get();
whereDate / whereMonth / whereDay / whereYear / whereTime
The whereDate
method may be used to compare a column's
value against a date:
$users = DB::table('users')
->whereDate('created_at', '2016-12-31')
->get();
The whereMonth
method may be used to compare a column's
value against a specific month of a year:
$users = DB::table('users')
->whereMonth('created_at', '12')
->get();
The whereDay
method may be used to compare a column's
value against a specific day of a month:
$users = DB::table('users')
->whereDay('created_at', '31')
->get();
The whereYear
method may be used to compare a column's
value against a specific year:
$users = DB::table('users')
->whereYear('created_at', '2016')
->get();
The whereTime
method may be used to compare a column's
value against a specific time:
$users = DB::table('users')
->whereTime('created_at', '=', '11:20')
->get();
whereColumn
The whereColumn
method may be used to verify that two
columns are equal:
$users = DB::table('users')
->whereColumn('first_name', 'last_name')
->get();
You may also pass a comparison operator to the method:
$users = DB::table('users')
->whereColumn('updated_at', '>', 'created_at')
->get();
The whereColumn
method can also be passed an array of
multiple conditions. These conditions will be joined using the
and
operator:
$users = DB::table('users')
->whereColumn([
['first_name', '=', 'last_name'],
['updated_at', '>', 'created_at']
])->get();
Parameter Grouping
Sometimes you may need to create more advanced where clauses such as "where exists" clauses or nested parameter groupings. The Laravel query builder can handle these as well. To get started, let's look at an example of grouping constraints within parenthesis:
DB::table('users')
->where('name', '=', 'John')
->orWhere(function ($query) {
$query->where('votes', '>', 100)
->where('title', '<>', 'Admin');
})
->get();
As you can see, passing a Closure
into the
orWhere
method instructs the query builder to begin a
constraint group. The Closure
will receive a query builder
instance which you can use to set the constraints that should be
contained within the parenthesis group. The example above will produce
the following SQL:
select * from users where name = 'John' or (votes > 100 and title <> 'Admin')
Where Exists Clauses
The whereExists
method allows you to write
where exists
SQL clauses. The whereExists
method accepts a Closure
argument, which will receive a
query builder instance allowing you to define the query that should be
placed inside of the "exists" clause:
DB::table('users')
->whereExists(function ($query) {
$query->select(DB::raw(1))
->from('orders')
->whereRaw('orders.user_id = users.id');
})
->get();
The query above will produce the following SQL:
select * from users
where exists (
select 1 from orders where orders.user_id = users.id
)
JSON Where Clauses
Laravel also supports querying JSON column types on databases that
provide support for JSON column types. Currently, this includes MySQL
5.7 and PostgreSQL. To query a JSON column, use the ->
operator:
$users = DB::table('users')
->where('options->language', 'en')
->get();
$users = DB::table('users')
->where('preferences->dining->meal', 'salad')
->get();
Ordering, Grouping, Limit, & Offset
orderBy
The orderBy
method allows you to sort the result of the
query by a given column. The first argument to the orderBy
method should be the column you wish to sort by, while the second
argument controls the direction of the sort and may be either
asc
or desc
:
$users = DB::table('users')
->orderBy('name', 'desc')
->get();
latest / oldest
The latest
and oldest
methods allow you to
easily order results by date. By default, result will be ordered by the
created_at
column. Or, you may pass the column name that
you wish to sort by:
$user = DB::table('users')
->latest()
->first();
inRandomOrder
The inRandomOrder
method may be used to sort the query
results randomly. For example, you may use this method to fetch a random
user:
$randomUser = DB::table('users')
->inRandomOrder()
->first();
groupBy / having
The groupBy
and having
methods may be used
to group the query results. The having
method's signature
is similar to that of the where
method:
$users = DB::table('users')
->groupBy('account_id')
->having('account_id', '>', 100)
->get();
You may pass multiple arguments to the groupBy
method to
group by multiple columns:
$users = DB::table('users')
->groupBy('first_name', 'status')
->having('account_id', '>', 100)
->get();
For more advanced having
statements, see the havingRaw
method.
skip / take
To limit the number of results returned from the query, or to skip a
given number of results in the query, you may use the skip
and take
methods:
$users = DB::table('users')->skip(10)->take(5)->get();
Alternatively, you may use the limit
and
offset
methods:
$users = DB::table('users')
->offset(10)
->limit(5)
->get();
Conditional Clauses
Sometimes you may want clauses to apply to a query only when
something else is true. For instance you may only want to apply a
where
statement if a given input value is present on the
incoming request. You may accomplish this using the when
method:
$role = $request->input('role');
$users = DB::table('users')
->when($role, function ($query) use ($role) {
return $query->where('role_id', $role);
})
->get();
The when
method only executes the given Closure when the
first parameter is true
. If the first parameter is
false
, the Closure will not be executed.
You may pass another Closure as the third parameter to the
when
method. This Closure will execute if the first
parameter evaluates as false
. To illustrate how this
feature may be used, we will use it to configure the default sorting of
a query:
$sortBy = null;
$users = DB::table('users')
->when($sortBy, function ($query) use ($sortBy) {
return $query->orderBy($sortBy);
}, function ($query) {
return $query->orderBy('name');
})
->get();
Inserts
The query builder also provides an insert
method for
inserting records into the database table. The insert
method accepts an array of column names and values:
DB::table('users')->insert(
['email' => 'john@example.com', 'votes' => 0]
);
You may even insert several records into the table with a single call
to insert
by passing an array of arrays. Each array
represents a row to be inserted into the table:
DB::table('users')->insert([
['email' => 'taylor@example.com', 'votes' => 0],
['email' => 'dayle@example.com', 'votes' => 0]
]);
Auto-Incrementing IDs
If the table has an auto-incrementing id, use the
insertGetId
method to insert a record and then retrieve the
ID:
$id = DB::table('users')->insertGetId(
['email' => 'john@example.com', 'votes' => 0]
);
Note: When using PostgreSQL the
insertGetId
method expects the auto-incrementing column to be namedid
. If you would like to retrieve the ID from a different "sequence", you may pass the column name as the second parameter to theinsertGetId
method.
Updates
Of course, in addition to inserting records into the database, the
query builder can also update existing records using the
update
method. The update
method, like the
insert
method, accepts an array of column and value pairs
containing the columns to be updated. You may constrain the
update
query using where
clauses:
DB::table('users')
->where('id', 1)
->update(['votes' => 1]);
Updating JSON Columns
When updating a JSON column, you should use ->
syntax
to access the appropriate key in the JSON object. This operation is only
supported on databases that support JSON columns:
DB::table('users')
->where('id', 1)
->update(['options->enabled' => true]);
Increment & Decrement
The query builder also provides convenient methods for incrementing
or decrementing the value of a given column. This is a shortcut,
providing a more expressive and terse interface compared to manually
writing the update
statement.
Both of these methods accept at least one argument: the column to modify. A second argument may optionally be passed to control the amount by which the column should be incremented or decremented:
DB::table('users')->increment('votes');
DB::table('users')->increment('votes', 5);
DB::table('users')->decrement('votes');
DB::table('users')->decrement('votes', 5);
You may also specify additional columns to update during the operation:
DB::table('users')->increment('votes', 1, ['name' => 'John']);
Deletes
The query builder may also be used to delete records from the table
via the delete
method. You may constrain
delete
statements by adding where
clauses
before calling the delete
method:
DB::table('users')->delete();
DB::table('users')->where('votes', '>', 100)->delete();
If you wish to truncate the entire table, which will remove all rows
and reset the auto-incrementing ID to zero, you may use the
truncate
method:
DB::table('users')->truncate();
Pessimistic Locking
The query builder also includes a few functions to help you do
"pessimistic locking" on your select
statements. To run the
statement with a "shared lock", you may use the sharedLock
method on a query. A shared lock prevents the selected rows from being
modified until your transaction commits:
DB::table('users')->where('votes', '>', 100)->sharedLock()->get();
Alternatively, you may use the lockForUpdate
method. A
"for update" lock prevents the rows from being modified or from being
selected with another shared lock:
DB::table('users')->where('votes', '>', 100)->lockForUpdate()->get();