Converting string to date. SQL

Question

I have table with column COL1(char 23) with full date eg '2007-11-13 12:34:49:012'. Now I want to change my date to '2007-11-12 59:59:59:999' (last moment in day before). Why the convert paremeters dont work property? My query:

convert(varchar(10),convert(date,DateAdd(day,-1,COL1),121)) + ' 23:59:59:999'

After

DateAdd(day,-1,COL1)

i get: "Nov 12 2007" and this is my problem. Finally i get: "Nov 12 200 23:59:59:999"

Answer 1

这个怎么样？

select dateadd(millisecond, -1, dateadd(day, 1, cast(left(col1, 10) as datetime)))

Answer 2

Varchar（10）不够灵通，无法尝试数据varchar（11）

Answer 3

尝试这个：

select cast(dateadd(ms, -1, cast(convert(varchar(8), cast(col1 as datetime), 112) as datetime2)) as varchar(23))