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Database: Query Builder
- Introduction
- Running Database Queries
- Select Statements
- Raw Expressions
- Joins
- Unions
- Basic Where Clauses
- Advanced Where Clauses
- Ordering, Grouping, Limit & Offset
- Conditional Clauses
- Insert Statements
- Update Statements
- Delete Statements
- Pessimistic Locking
- Debugging
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 perfectly with all of Laravel's 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 or sanitize strings passed to the query builder as query bindings.
{note} PDO does not support binding column names. Therefore, you should never allow user input to dictate the column names referenced by your queries, including "order by" columns.
Running Database Queries
Retrieving All Rows From A Table
You may use the
table
method provided by theDB
facade to begin a query. Thetable
method returns a fluent query builder instance for the given table, allowing you to chain more constraints onto the query and then finally retrieve the results of the query using theget
method:<?php namespace App\Http\Controllers; use App\Http\Controllers\Controller; use Illuminate\Support\Facades\DB; class UserController extends Controller { /** * Show a list of all of the application's users. * * @return \Illuminate\Http\Response */ public function index() { $users = DB::table('users')->get(); return view('user.index', ['users' => $users]); } }
The
get
method returns anIlluminate\Support\Collection
containing the results of the query where each result is an instance of the PHPstdClass
object. You may access each column's value by accessing the column as a property of the object:use Illuminate\Support\Facades\DB; $users = DB::table('users')->get(); foreach ($users as $user) { echo $user->name; }
{tip} Laravel collections provide a variety of extremely powerful methods for mapping and reducing data. For more information on Laravel collections, check out the collection documentation.
Retrieving A Single Row / Column From A Table
If you just need to retrieve a single row from a database table, you may use the
DB
facade'sfirst
method. This method will return a singlestdClass
object:$user = DB::table('users')->where('name', 'John')->first(); return $user->email;
If you don't need an entire row, you may extract a single value from a record using the
value
method. This method will return the value of the column directly:$email = DB::table('users')->where('name', 'John')->value('email');
To retrieve a single row by its
id
column value, use thefind
method:$user = DB::table('users')->find(3);
Retrieving A List Of Column Values
If you would like to retrieve an
Illuminate\Support\Collection
instance containing the values of a single column, you may use thepluck
method. In this example, we'll retrieve a collection of role titles:use Illuminate\Support\Facades\DB; $titles = DB::table('users')->pluck('title'); foreach ($titles as $title) { echo $title; }
You may specify the column that the resulting collection should use as its keys by providing a second argument to the
pluck
method:$titles = DB::table('users')->pluck('title', 'name'); foreach ($titles as $name => $title) { echo $title; }
Chunking Results
If you need to work with thousands of database records, consider using the
chunk
method provided by theDB
facade. This method retrieves a small chunk of results at a time and feeds each chunk into a closure for processing. For example, let's retrieve the entireusers
table in chunks of 100 records at a time:use Illuminate\Support\Facades\DB; DB::table('users')->orderBy('id')->chunk(100, function ($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; });
If you are updating database records while chunking results, your chunk results could change in unexpected ways. If you plan to update the retrieved records while chunking, it is always best to use the
chunkById
method instead. This method will automatically paginate the results based on the record's primary key:DB::table('users')->where('active', false) ->chunkById(100, function ($users) { foreach ($users as $user) { DB::table('users') ->where('id', $user->id) ->update(['active' => true]); } });
{note} When updating or deleting records inside the chunk callback, any changes to the primary key or foreign keys could affect the chunk query. This could potentially result in records not being included in the chunked results.
Aggregates
The query builder also provides a variety of methods for retrieving aggregate values like
count
,max
,min
,avg
, andsum
. You may call any of these methods after constructing your query:use Illuminate\Support\Facades\DB; $users = DB::table('users')->count(); $price = DB::table('orders')->max('price');
Of course, you may combine these methods with other clauses to fine-tune how your aggregate value is calculated:
$price = DB::table('orders') ->where('finalized', 1) ->avg('price');
Determining If Records Exist
Instead of using the
count
method to determine if any records exist that match your query's constraints, you may use theexists
anddoesntExist
methods:if (DB::table('orders')->where('finalized', 1)->exists()) { // ... } if (DB::table('orders')->where('finalized', 1)->doesntExist()) { // ... }
Select Statements
Specifying A Select Clause
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:use Illuminate\Support\Facades\DB; $users = DB::table('users') ->select('name', 'email as user_email') ->get();
The
distinct
method allows you to force the query to return distinct results:$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 = $query->addSelect('age')->get();
Raw Expressions
Sometimes you may need to insert an arbitrary string into a query. To create a raw string expression, you may use the
raw
method provided by theDB
facade:$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 avoid creating SQL injection vulnerabilities.
Raw Methods
Instead of using the
DB::raw
method, you may also use the following methods to insert a raw expression into various parts of your query. Remember, Laravel can not guarantee that any query using raw expressions is protected against SQL injection vulnerabilities.
selectRaw
The
selectRaw
method can be used in place ofaddSelect(DB::raw(...))
. This method accepts an optional array of bindings as its second argument:$orders = DB::table('orders') ->selectRaw('price * ? as price_with_tax', [1.0825]) ->get();
whereRaw / orWhereRaw
The
whereRaw
andorWhereRaw
methods can be used to inject a raw "where" clause into your query. These methods accept an optional array of bindings as their second argument:$orders = DB::table('orders') ->whereRaw('price > IF(state = "TX", ?, 100)', [200]) ->get();
havingRaw / orHavingRaw
The
havingRaw
andorHavingRaw
methods may be used to provide a raw string as the value of the "having" clause. These methods accept an optional array of bindings as their second argument:$orders = DB::table('orders') ->select('department', DB::raw('SUM(price) as total_sales')) ->groupBy('department') ->havingRaw('SUM(price) > ?', [2500]) ->get();
orderByRaw
The
orderByRaw
method may be used to provide a raw string as the value of the "order by" clause:$orders = DB::table('orders') ->orderByRaw('updated_at - created_at DESC') ->get();
groupByRaw
The
groupByRaw
method may be used to provide a raw string as the value of thegroup by
clause:$orders = DB::table('orders') ->select('city', 'state') ->groupByRaw('city, state') ->get();
Joins
Inner Join Clause
The query builder may also be used to add join clauses to your queries. To perform a basic "inner join", you may use the
join
method on a query builder instance. The first argument passed to thejoin
method is the name of the table you need to join to, while the remaining arguments specify the column constraints for the join. You may even join multiple tables in a single query:use Illuminate\Support\Facades\DB; $users = DB::table('users') ->join('contacts', 'users.id', '=', 'contacts.user_id') ->join('orders', 'users.id', '=', 'orders.user_id') ->select('users.*', 'contacts.phone', 'orders.price') ->get();
Left Join / Right Join Clause
If you would like to perform a "left join" or "right join" instead of an "inner join", use the
leftJoin
orrightJoin
methods. These methods have the same signature as thejoin
method:$users = DB::table('users') ->leftJoin('posts', 'users.id', '=', 'posts.user_id') ->get(); $users = DB::table('users') ->rightJoin('posts', 'users.id', '=', 'posts.user_id') ->get();
Cross Join Clause
You may use the
crossJoin
method to perform a "cross join". Cross joins generate a cartesian product between the first table and the joined table:$sizes = DB::table('sizes') ->crossJoin('colors') ->get();
Advanced Join Clauses
You may also specify more advanced join clauses. To get started, pass a closure as the second argument to the
join
method. The closure will receive aIlluminate\Database\Query\JoinClause
instance which allows you to specify constraints on the "join" clause:DB::table('users') ->join('contacts', function ($join) { $join->on('users.id', '=', 'contacts.user_id')->orOn(...); }) ->get();
If you would like to use a "where" clause on your joins, you may use the
where
andorWhere
methods provided by theJoinClause
instance. Instead of comparing two columns, these methods will compare the column against a value:DB::table('users') ->join('contacts', function ($join) { $join->on('users.id', '=', 'contacts.user_id') ->where('contacts.user_id', '>', 5); }) ->get();
Subquery Joins
You may use the
joinSub
,leftJoinSub
, andrightJoinSub
methods to join a query to a subquery. Each of these methods receives three arguments: the subquery, its table alias, and a closure that defines the related columns. In this example, we will retrieve a collection of users where each user record also contains thecreated_at
timestamp of the user's most recently published blog post:$latestPosts = DB::table('posts') ->select('user_id', DB::raw('MAX(created_at) as last_post_created_at')) ->where('is_published', true) ->groupBy('user_id'); $users = DB::table('users') ->joinSub($latestPosts, 'latest_posts', function ($join) { $join->on('users.id', '=', 'latest_posts.user_id'); })->get();
Unions
The query builder also provides a convenient method to "union" two or more queries together. For example, you may create an initial query and use the
union
method to union it with more queries:use Illuminate\Support\Facades\DB; $first = DB::table('users') ->whereNull('first_name'); $users = DB::table('users') ->whereNull('last_name') ->union($first) ->get();
In addition to the
union
method, the query builder provides aunionAll
method. Queries that are combined using theunionAll
method will not have their duplicate results removed. TheunionAll
method has the same method signature as theunion
method.Basic Where Clauses
Where Clauses
You may use the query builder's
where
method to add "where" clauses to the query. The most basic call to thewhere
method 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. The third argument is the value to compare against the column's value.For example, the following query retrieves users where the value of the
votes
column is equal to100
and the value of theage
column is greater than35
:$users = DB::table('users') ->where('votes', '=', 100) ->where('age', '>', 35) ->get();
For convenience, if you want to verify that a column is
=
to a given value, you may pass the value as the second argument to thewhere
method. Laravel will assume you would like to use the=
operator:$users = DB::table('users')->where('votes', 100)->get();
As previously mentioned, you may use any operator that is supported by your database system:
$users = DB::table('users') ->where('votes', '>=', 100) ->get(); $users = DB::table('users') ->where('votes', '<>', 100) ->get(); $users = DB::table('users') ->where('name', 'like', 'T%') ->get();
You may also pass an array of conditions to the
where
function. Each element of the array should be an array containing the three arguments typically passed to thewhere
method:$users = DB::table('users')->where([ ['status', '=', '1'], ['subscribed', '<>', '1'], ])->get();
Or Where Clauses
When chaining together calls to the query builder's
where
method, the "where" clauses will be joined together using theand
operator. However, you may use theorWhere
method to join a clause to the query using theor
operator. TheorWhere
method accepts the same arguments as thewhere
method:$users = DB::table('users') ->where('votes', '>', 100) ->orWhere('name', 'John') ->get();
If you need to group an "or" condition within parentheses, you may pass a closure as the first argument to the
orWhere
method:$users = DB::table('users') ->where('votes', '>', 100) ->orWhere(function($query) { $query->where('name', 'Abigail') ->where('votes', '>', 50); }) ->get();
The example above will produce the following SQL:
select * from users where votes > 100 or (name = 'Abigail' and votes > 50)
{note} You should always group
orWhere
calls in order to avoid unexpected behavior when global scopes are applied.JSON Where Clauses
Laravel also supports querying JSON column types on databases that provide support for JSON column types. Currently, this includes MySQL 5.7+, PostgreSQL, SQL Server 2016, and SQLite 3.9.0 (with the JSON1 extension). To query a JSON column, use the
->
operator:$users = DB::table('users') ->where('preferences->dining->meal', 'salad') ->get();
You may use
whereJsonContains
to query JSON arrays. This feature is not supported by the SQLite database:$users = DB::table('users') ->whereJsonContains('options->languages', 'en') ->get();
If your application uses the MySQL or PostgreSQL databases, you may pass an array of values to the
whereJsonContains
method:$users = DB::table('users') ->whereJsonContains('options->languages', ['en', 'de']) ->get();
You may use
whereJsonLength
method to query JSON arrays by their length:$users = DB::table('users') ->whereJsonLength('options->languages', 0) ->get(); $users = DB::table('users') ->whereJsonLength('options->languages', '>', 1) ->get();
Additional Where Clauses
whereBetween / orWhereBetween
The
whereBetween
method verifies that a column's value is between two values:$users = DB::table('users') ->whereBetween('votes', [1, 100]) ->get();
whereNotBetween / orWhereNotBetween
The
whereNotBetween
method verifies that a column's value lies outside of two values:$users = DB::table('users') ->whereNotBetween('votes', [1, 100]) ->get();
whereIn / whereNotIn / orWhereIn / orWhereNotIn
The
whereIn
method verifies that a given column's value is contained within the given array:$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:$users = DB::table('users') ->whereNotIn('id', [1, 2, 3]) ->get();
{note} If you are adding a large array of integer bindings to your query, the
whereIntegerInRaw
orwhereIntegerNotInRaw
methods may be used to greatly reduce your memory usage.whereNull / whereNotNull / orWhereNull / orWhereNotNull
The
whereNull
method verifies that the value of the given column isNULL
:$users = DB::table('users') ->whereNull('updated_at') ->get();
The
whereNotNull
method verifies that the column's value is notNULL
:$users = DB::table('users') ->whereNotNull('updated_at') ->get();
whereDate / whereMonth / whereDay / whereYear / whereTime
The
whereDate
method may be used to compare a column's value against a date:$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:$users = DB::table('users') ->whereMonth('created_at', '12') ->get();
The
whereDay
method may be used to compare a column's value against a specific day of the month:$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', '=', '11:20:45') ->get();
whereColumn / orWhereColumn
The
whereColumn
method may be used to verify that two columns are equal:$users = DB::table('users') ->whereColumn('first_name', 'last_name') ->get();
You may also pass a comparison operator to the
whereColumn
method:$users = DB::table('users') ->whereColumn('updated_at', '>', 'created_at') ->get();
You may also pass an array of column comparisons to the
whereColumn
method. These conditions will be joined using theand
operator:$users = DB::table('users') ->whereColumn([ ['first_name', '=', 'last_name'], ['updated_at', '>', 'created_at'], ])->get();
Logical Grouping
Sometimes you may need to group several "where" clauses within parentheses in order to achieve your query's desired logical grouping. In fact, you should generally always group calls to the
orWhere
method in parentheses in order to avoid unexpected query behavior. To accomplish this, you may pass a closure to thewhere
method:$users = DB::table('users') ->where('name', '=', 'John') ->where(function ($query) { $query->where('votes', '>', 100) ->orWhere('title', '=', 'Admin'); }) ->get();
As you can see, passing a closure into the
where
method instructs the query builder to begin a constraint group. The closure will receive a query builder instance which you can use to set the constraints that should be contained within the parenthesis group. The example above will produce the following SQL:select * from users where name = 'John' and (votes > 100 or title = 'Admin')
{note} You should always group
orWhere
calls in order to avoid unexpected behavior when global scopes are applied.Advanced Where Clauses
Where Exists Clauses
The
whereExists
method allows you to write "where exists" SQL clauses. ThewhereExists
method accepts a closure which will receive a query builder instance, allowing you to define the query that should be placed inside of the "exists" clause:$users = DB::table('users') ->whereExists(function ($query) { $query->select(DB::raw(1)) ->from('orders') ->whereColumn('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 )
Subquery Where Clauses
Sometimes you may need to construct a "where" clause that compares the results of a subquery to a given value. You may accomplish this by passing a closure and a value to the
where
method. For example, the following query will retrieve all users who have a recent "membership" of a given type;use App\Models\User; $users = User::where(function ($query) { $query->select('type') ->from('membership') ->whereColumn('membership.user_id', 'users.id') ->orderByDesc('membership.start_date') ->limit(1); }, 'Pro')->get();
Or, you may need to construct a "where" clause that compares a column to the results of a subquery. You may accomplish this by passing a column, operator, and closure to the
where
method. For example, the following query will retrieve all income records where the amount is less than average;use App\Models\Income; $incomes = Income::where('amount', '<', function ($query) { $query->selectRaw('avg(i.amount)')->from('incomes as i'); })->get();
Ordering, Grouping, Limit & Offset
Ordering
The
orderBy
MethodThe
orderBy
method allows you to sort the results of the query by a given column. The first argument accepted by theorderBy
method should be the column you wish to sort by, while the second argument determines the direction of the sort and may be eitherasc
ordesc
:$users = DB::table('users') ->orderBy('name', 'desc') ->get();
To sort by multiple columns, you may simply invoke
orderBy
as many times as necessary:$users = DB::table('users') ->orderBy('name', 'desc') ->orderBy('email', 'asc') ->get();
The
latest
&oldest
MethodsThe
latest
andoldest
methods allow you to easily order results by date. By default, the result will be ordered by the table'screated_at
column. Or, you may pass the column name that you wish to sort by:$user = DB::table('users') ->latest() ->first();
Random Ordering
The
inRandomOrder
method may be used to sort the query results randomly. For example, you may use this method to fetch a random user:$randomUser = DB::table('users') ->inRandomOrder() ->first();
Removing Existing Orderings
The
reorder
method removes all of the "order by" clauses that have previously been applied to the query:$query = DB::table('users')->orderBy('name'); $unorderedUsers = $query->reorder()->get();
You may pass a column and direction when calling the
reorder
method in order to remove all existing "order by "clauses" and apply an entirely new order to the query:$query = DB::table('users')->orderBy('name'); $usersOrderedByEmail = $query->reorder('email', 'desc')->get();
Grouping
The
groupBy
&having
MethodsAs you might expect, the
groupBy
andhaving
methods may be used to group the query results. Thehaving
method's signature is similar to that of thewhere
method:$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:$users = DB::table('users') ->groupBy('first_name', 'status') ->having('account_id', '>', 100) ->get();
To build more advanced
having
statements, see thehavingRaw
method.Limit & Offset
The
skip
&take
MethodsYou may use the
skip
andtake
methods to limit the number of results returned from the query or to skip a given number of results in the query:$users = DB::table('users')->skip(10)->take(5)->get();
Alternatively, you may use the
limit
andoffset
methods. These methods are functionally equivalent to thetake
andskip
methods, respectively:$users = DB::table('users') ->offset(10) ->limit(5) ->get();
Conditional Clauses
Sometimes you may want certain query clauses to apply to a query based on another condition. For instance, you may only want to apply a
where
statement if a given input value is present on the incoming HTTP request. You may accomplish this using thewhen
method:$role = $request->input('role'); $users = DB::table('users') ->when($role, function ($query, $role) { return $query->where('role_id', $role); }) ->get();
The
when
method only executes the given closure when the first argument istrue
. If the first argument isfalse
, the closure will not be executed. So, in the example above, the closure given to thewhen
method will only be invoked if therole
field is present on the incoming request and evaluates totrue
.You may pass another closure as the third argument to the
when
method. This closure will only execute if the first argument evaluates asfalse
. To illustrate how this feature may be used, we will use it to configure the default ordering of a query:$sortByVotes = $request->input('sort_by_votes'); $users = DB::table('users') ->when($sortByVotes, function ($query, $sortByVotes) { return $query->orderBy('votes'); }, function ($query) { return $query->orderBy('name'); }) ->get();
Insert Statements
The query builder also provides an
insert
method that may be used to insert records into the database table. Theinsert
method accepts an array of column names and values:DB::table('users')->insert([ 'email' => '[email protected]', 'votes' => 0 ]);
You may insert several records at once by passing an array of arrays. Each array represents a record that should be inserted into the table:
DB::table('users')->insert([ ['email' => '[email protected]', 'votes' => 0], ['email' => '[email protected]', 'votes' => 0], ]);
The
insertOrIgnore
method will ignore duplicate record errors while inserting records into the database:DB::table('users')->insertOrIgnore([ ['id' => 1, 'email' => '[email protected]'], ['id' => 2, 'email' => '[email protected]'], ]);
Auto-Incrementing IDs
If the table has an auto-incrementing id, use the
insertGetId
method to insert a record and then retrieve the ID:$id = DB::table('users')->insertGetId( ['email' => '[email protected]', '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.Upserts
The
upsert
method will insert records that do not exist and update the records that already exist with new values that you may specify. The method's first argument consists of the values to insert or update, while the second argument lists the column(s) that uniquely identify records within the associated table. The method's third and final argument is an array of columns that should be updated if a matching record already exists in the database:DB::table('flights')->upsert([ ['departure' => 'Oakland', 'destination' => 'San Diego', 'price' => 99], ['departure' => 'Chicago', 'destination' => 'New York', 'price' => 150] ], ['departure', 'destination'], ['price']);
In the example above, Laravel will attempt to insert two records. If a record already exists with the same
departure
anddestination
column values, Laravel will update that record'sprice
column.{note} All databases except SQL Server require the columns in the second argument of the
upsert
method to have a "primary" or "unique" index.Update Statements
In addition to inserting records into the database, the query builder can also update existing records using the
update
method. Theupdate
method, like theinsert
method, accepts an array of column and value pairs indicating the columns to be updated. You may constrain theupdate
query usingwhere
clauses:$affected = DB::table('users') ->where('id', 1) ->update(['votes' => 1]);
Update Or Insert
Sometimes you may want to update an existing record in the database or create it if no matching record exists. In this scenario, the
updateOrInsert
method may be used. TheupdateOrInsert
method accepts two arguments: an array of conditions by which to find the record, and an array of column and value pairs indicating the columns to be updated.The
updateOrInsert
method will attempt to locate a matching database record using the first argument's column and value pairs. If the record exists, it will be updated with the values in the second argument. If the record can not be found, a new record will be inserted with the merged attributes of both arguments:DB::table('users') ->updateOrInsert( ['email' => '[email protected]', 'name' => 'John'], ['votes' => '2'] );
Updating JSON Columns
When updating a JSON column, you should use
->
syntax to update the appropriate key in the JSON object. This operation is supported on MySQL 5.7+ and PostgreSQL 9.5+:$affected = 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. Both of these methods accept at least one argument: the column to modify. A second argument may be provided to specify 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']);
Delete Statements
The query builder's
delete
method may be used to delete records from the table. You may constraindelete
statements by adding "where" clauses before calling thedelete
method:DB::table('users')->delete(); DB::table('users')->where('votes', '>', 100)->delete();
If you wish to truncate an entire table, which will remove all records from the table and reset the auto-incrementing ID to zero, you may use the
truncate
method:DB::table('users')->truncate();
Table Truncation & PostgreSQL
When truncating a PostgreSQL database, the
CASCADE
behavior will be applied. This means that all foreign key related records in other tables will be deleted as well.Pessimistic Locking
The query builder also includes a few functions to help you achieve "pessimistic locking" when executing your
select
statements. To execute a statement with a "shared lock", you may call thesharedLock
method. A shared lock prevents the selected rows from being modified until your transaction is committed:DB::table('users') ->where('votes', '>', 100) ->sharedLock() ->get();
Alternatively, you may use the
lockForUpdate
method. A "for update" lock prevents the selected records from being modified or from being selected with another shared lock:DB::table('users') ->where('votes', '>', 100) ->lockForUpdate() ->get();
Debugging
You may use the
dd
anddump
methods while building a query to dump the current query bindings and SQL. Thedd
method will display the debug information and then stop executing the request. Thedump
method will display the debug information but allow the request to continue executing:DB::table('users')->where('votes', '>', 100)->dd(); DB::table('users')->where('votes', '>', 100)->dump();