MS SQL add Update Statistics job (Schedule) to get better performance ( Reindexing )

/****** Object: Job [Update CRM Statistics] Script Date: 05/01/2017 09:43:42 ******/
 BEGIN TRANSACTION
 DECLARE @ReturnCode INT
 SELECT @ReturnCode = 0
 /****** Object: JobCategory [[Uncategorized (Local)]]] Script Date: 05/01/2017 09:43:43 ******/
 IF NOT EXISTS (SELECT name FROM msdb.dbo.syscategories WHERE name=N'[Uncategorized (Local)]' AND category_class=1)
 BEGIN
 EXEC @ReturnCode = msdb.dbo.sp_add_category @class=N'JOB', @type=N'LOCAL', @name=N'[Uncategorized (Local)]'
 IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback

END

DECLARE @jobId BINARY(16)
 EXEC @ReturnCode = msdb.dbo.sp_add_job @job_name=N'Update CRM Statistics',
 @enabled=1,
 @notify_level_eventlog=3,
 @notify_level_email=0,
 @notify_level_netsend=0,
 @notify_level_page=0,
 @delete_level=0,
 @description=N'No description available.',
 @category_name=N'[Uncategorized (Local)]',
 @owner_login_name=N'xxxx', @job_id = @jobId OUTPUT

/*xxxx = login username for the database which has dbaadmin permission*/
 IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
 /****** Object: Step [Update Statistics] Script Date: 05/01/2017 09:43:43 ******/
 EXEC @ReturnCode = msdb.dbo.sp_add_jobstep @job_id=@jobId, @step_name=N'Update Statistics',
 @step_id=1,
 @cmdexec_success_code=0,
 @on_success_action=1,
 @on_success_step_id=0,
 @on_fail_action=2,
 @on_fail_step_id=0,
 @retry_attempts=0,
 @retry_interval=0,
 @os_run_priority=0, @subsystem=N'TSQL',
 @command=N'DECLARE @tablename varchar(80),@shemaname varchar(80)
 DECLARE @SQL AS NVARCHAR(200)
 DECLARE TblName_cursor CURSOR FOR
 SELECT t.name,s.name FROM sys.tables t join sys.schemas s
 on s.schema_id=t.schema_id
 OPEN TblName_cursor

FETCH NEXT FROM TblName_cursor
 INTO @tablename,@shemaname

WHILE @@FETCH_STATUS = 0
 BEGIN
 SET @SQL = ''UPDATE STATISTICS ''+@shemaname+''.['' + @TableName + ''] WITH FULLSCAN '' ---+ CONVERT(varchar(3), @sample) + '' PERCENT''
 PRINT @SQL

EXEC sp_executesql @statement = @SQL

FETCH NEXT FROM TblName_cursor
 INTO @tablename,@shemaname
 END

CLOSE TblName_cursor
 DEALLOCATE TblName_cursor
 ',
 @database_name=N'CRM',

/*CRM is the database NAME*/
 @flags=0
 IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
 EXEC @ReturnCode = msdb.dbo.sp_update_job @job_id = @jobId, @start_step_id = 1
 IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
 EXEC @ReturnCode = msdb.dbo.sp_add_jobschedule @job_id=@jobId, @name=N'Reindexing',
 @enabled=1,
 @freq_type=4,
 @freq_interval=1,
 @freq_subday_type=1,
 @freq_subday_interval=0,
 @freq_relative_interval=0,
 @freq_recurrence_factor=0,
 @active_start_date=20141124,
 @active_end_date=99991231,
 @active_start_time=193000,
 @active_end_time=235959,
 @schedule_uid=N'b5ec9450-ee63-43bc-926f-ab5e36d5dc9e'
 IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
 EXEC @ReturnCode = msdb.dbo.sp_add_jobserver @job_id = @jobId, @server_name = N'(local)'
 IF (@@ERROR <> 0 OR @ReturnCode <> 0) GOTO QuitWithRollback
 COMMIT TRANSACTION
 GOTO EndSave
 QuitWithRollback:
 IF (@@TRANCOUNT > 0) ROLLBACK TRANSACTION
 EndSave:

GO