IF COL_LENGTH('dbo.asr_wrk_mast', 'cost_time') IS NULL
BEGIN
    ALTER TABLE [dbo].[asr_wrk_mast]
        ADD [cost_time] INT NULL;
END
GO

IF COL_LENGTH('dbo.asr_wrk_mast_log', 'cost_time') IS NULL
BEGIN
    ALTER TABLE [dbo].[asr_wrk_mast_log]
        ADD [cost_time] INT NULL;
END
GO