在Cognos report Studio中将具有整数数据类型的列转换为日期

Question

I have a column that appear like this and the data type is integer. I get that data from AS400 server that's why it uses integer data type. The date format is represent as YYYYMMDD

In report studio, I created a data item that would convert this integer column to date time. But it failed.

I have tried lots of different approach but none of these worked.

cast([WCPDOD], 'YYYYMMDD')

cast([WCPDOD], date) UDA-SQL-0219 The function "to_date" is being used for local processing but is not available as a built-in function, or at least one of its parameters is not supported.RSV-SRV-0042

cast([WCPDOD], YYYY-MM-DD)

cast([WCPDOD], datetime)

cast_timestamp([WCPDOD], datetime)

cast_timestamp([WCPDOD], date)

cast_integer([WCPDOD], date)

Can someone help me with this? My goal is to get this 20150729 into this 07/29/2015 at least

Answer 1

First, cast your 10-digit integer into a string:

Data Item2

cast([Data Item1],varchar(10))

Next, use substring to extract out the date components and build a date string:

Data Item3

substring([Data Item2],1,4) + '-' + substring([Data Item2],5,2) + '-' + substring([Data Item2],7,2)

Lastly, convert the resulting string to date format:

Data Item4

cast([Data Item3],date)

Of course, this can all be done in a single expression but I broke it out here for clarity.

Answer 2

In SQL Server, you can convert the integer field to varchar and then to a date and then use the date style 101 to achieve your desired format:

DECLARE @datevalue int = '20150729';

SELECT convert(varchar(10),cast(cast(@datevalue AS varchar(10)) as date), 101);