Laravel Eloquent Postgresql Select with Case，然后按Case结果过滤

$result = DB::table('table_name')
    ->select('column1', 'column2', 'column3')
    ->where(function ($query) {
        $query->when(condition1, function ($query) {
            return $query->where('column1', 'value1');
        })
        ->when(condition2, function ($query) {
            return $query->where('column2', 'value2');
        })
        ->when(condition3, function ($query) {
            return $query->where('column3', 'value3');
        });
    })
    ->get();

$result = DB::table('table_name')
    ->select('column1', 'column2', 'column3')
    ->where(function ($query) {
        $query->whereRaw("CASE 
            WHEN column1 = 'value1' THEN column2 = 'value2'
            WHEN column1 = 'value3' THEN column3 = 'value4'
            ELSE column2 = 'value5'
            END");
    })
    ->get();