Query Builder

Database: Query Builder

• consistentRead
• condition
• decrement
• delete
• fetch
• from
• filter
• first
• find
• increment
• insert
• insertOrReplace
• whereKey
• whereKeyBetween
• whereKeyBeginsWith
• key
• limit
• putItem
• select
• scanFromBackward
• orFilter
• raw
• query
• scan
• update

Retrieving All Rows From A Table

You may use the table method provided by 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 retrieve the results of the query using the scan method:

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()
    {
        // Scan operation
        $users = DB::table('users')->scan();
        
        // Query Operation
        $users = DB::table('users')->keyCondtion('PK', 'USERS')->query();

        return view('user.index', ['users' => $users]);
    }
}

Consistent Read

Determines the read consistency model: If set to true, then the operation uses strongly consistent reads; otherwise, the operation uses eventually consistent reads.

Strongly consistent reads are not supported on global secondary indexes. If you query a global secondary index with ConsistentRead set to true, you will receive a ValidationException.

Type: Boolean

DB::table('users')->consistentRead(true)->keyCondtion('PK', 'USERS')->query();

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')->key(['id' => 'id-1'])->increment('votes');

DB::table('users')->key(['id' => 'id-1'])->increment('votes', 5);

DB::table('users')->key(['id' => 'id-1'])->decrement('votes');

DB::table('users')->key(['id' => 'id-1'])->decrement('votes', 5);

You may also specify additional columns to update during the operation:

DB::table('users')->key(['id' => 'id-1'])->increment('votes', 1, ['name' => 'John']);

You may also specify add or set mode, by default increment or decrement, is using set mode. But you can add the prefix add: to use add mode.

DB::table('users')->key(['id' => 'id-1'])->decrement('add:votes', 5);

Insert Statements

The query builder also provides an insert method that may be used to insert records into the database table. The insert method accepts an array of column names and values:

DB::table('users')->insert([
    'email' => 'kayla@example.com',
    'votes' => 0
]);

Update Statements

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 indicating the columns to be updated. You may constrain the update query using key method:

DB::table('users')->key(['id' => 'id-1'])->update([
    'votes' => 5
]);

Delete Statements

The query builder's delete method may be used to delete records from the table. You may constrain delete statements by adding "key" method before calling the delete method:

DB::table('users')->key(['id' => 'id-1'])->delete();