Laravel query builder use PDO parameter bindings but PDO does not support binding column name.

Retrieve all results form a table:

$users=DB::table('users')->get();
return $users;

Retrieve all result of specific column name

$users=DB::table('users')->pluck('name');
return $users;

Using where clause to get all result:

$users=DB::table('users')->where('name',"Navid")->get();
return $users;

Retrieve a Single Row from a table:

$users=DB::table('users')->first();
return $users; 

Retrieve a single row with where clause:

$users=DB::table('users')->where('name',"Navid")->first();
return $users;

Retrieve a single row by its id:

$users=DB::table('users')->find(1);
return $users;

Chunking Result:

If we have thousand of result, we may want to get 100 records each time

DB::table(‘users’)->orderBy(‘id’)->chunk(100,function($users){

foreach($users as $user){
}});

We may strop further chunks from going forward using returning false

DB::table(‘users’)->orderBy(‘id’)->chunk(100,function($users){

foreach($users as $user){

return false;
}});

If update and chunk are occurring at the same time it may cause some unexpected behavior.If we plan to update the record while chunk, we should use chunkbyid

Lazy Method:

Lazy Method returns the result as chunk but we can interact the result one by one.

DB::table(‘users’)->orderby(‘id’)->lazy()->each(function ($user){

});

If we plan to update the record using Lazy Method, we should use LazyByID

DB::table(‘users’)->where(‘name’,”navid”)

->LazyByID()->each(function($user){

});

Aggregates:

Query Builder also support count, max, min, avg and sum.

DB::table(‘users’)->count(‘id’);

DB::table('users')->max('id');DB::table(‘users’)->min(‘id’);DB::table(‘users’)->avg(‘price’);DB::table(‘user’)->sum(‘price’);

Find the record if exist or doesntExist. It will return true or false

$user= DB::table('users')->where('name','Hri')->exists();$user= DB::table('users')->where('name','Hri')-> doesntExist();

Select statement:

$user=DB::table('users')
    ->select('name','id')
    ->get();

Getting Distinct Value:

DB::table('users')
    ->distinct()
    ->get();

Adding additional column:

$firstQuery=DB::table('users')->select('name');
$querytwo=$firstQuery->addSelect('id')->get();

return $querytwo;

We can sent the string using DB::raw.

  $string='count(*) as id, name';
  $users = DB::table('users')
->select(DB::raw($string))
->where('name', '=', "Hri")
->groupBy('name')
->get();

Note: Raw statements will be added as strings, so we should avoid creating SQL injection vulnerabilities.

Also check out the other blog ..

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For more info:https://laravel.com/docs/8.x/queries