IF COL_LENGTH('dbo.asr_wrk_mast', 'batch_seq') IS NULL
BEGIN
    ALTER TABLE [dbo].[asr_wrk_mast]
        ADD [batch_seq] NVARCHAR(100) NULL;
END
ELSE
BEGIN
    ALTER TABLE [dbo].[asr_wrk_mast]
        ALTER COLUMN [batch_seq] NVARCHAR(100) NULL;
END
GO

IF COL_LENGTH('dbo.asr_wrk_mast_log', 'batch_seq') IS NULL
BEGIN
    ALTER TABLE [dbo].[asr_wrk_mast_log]
        ADD [batch_seq] NVARCHAR(100) NULL;
END
ELSE
BEGIN
    ALTER TABLE [dbo].[asr_wrk_mast_log]
        ALTER COLUMN [batch_seq] NVARCHAR(100) NULL;
END
GO