sql字符串根据日期产生日期+自增长标志

select Convert(varchar(6), '20180614 20:19:04', 12) +
SubString('0000' + Convert(varchar(6), 1 + 1), len('0000' + Convert(varchar(8), 1 + 1)) - 3, 4)

Convert(varchar(6), @Today, 12) +
SubString(''0000'' + Convert(varchar(8), @BegNo + Cou), len(''0000'' + Convert(varchar(8), @BegNo + Cou)) - 3, 4)