Converting CYYMMDD to SAS Date in DB2 via SAS - sql

Question

I'm looking to convert a date that is in the format of CYYMMDD (where C is either 0 for 20th century or 1 for 21st century) to a standard SAS date. This code will be placed inside of a SAS query using 'proc sql' so that it can compare a SAS date against a date stored in DB2.
Example: Input data=1130101, Output='1Jan2013'd
Examples I've tried are:
(substr(t1.'EffectDate'n,4,2)|| '/' || substr(t1.'EffectDate'n,6,2) || '/' || cast(substr(t1.'EffectDate'n,1,3) AS INTEGER) + 1900)
That fails to the cast() function (appears it doesn't exist?)
Also tried:
convert(varchar(10), convert(datetime, right(t1.'EffectDate'n, 6), 12), 101)
But varchar(10) doesn't exist.
My query looks like this:
proc sql;
create table CLAIMS as select
t1.CID,
t1.MID,
t1.DOS
OTHER_TABLE.ChangeDate AS EffectDate
FROM
SOURCE.REJECTED t1
INNER JOIN
EGTASK.OTHER_TABLE
ON
t1.DOS >= *Converted_Date*
[... goes on a couple more lines...]
Where *Converted_Date* is what I need.
(However, I should clarify that this particular query/join doesn't necessarily need to be SQL)

Answer 1

To convert your variable from it's current coded format into a proper SAS date variable, you will need to turn it into a character string and then read the result using the INPUT function. For example:
data _null_;
do EffectDate = 1130101,0130101;
cEffectDate = put(EffectDate,z7.);
if substr(cEffectDate,1,1) = '0'
then SASEffectDate = input('19' || substr(cEffectDate,2),yymmdd8.);
else SASEffectDate = input('20' || substr(cEffectDate,2),yymmdd8.);
put EffectDate=
/ SASEffectDate=
/ ;
end;
format SASEffectDate yymmdd10.;
run;
This is just an illustration and a bit long-winded; it creates a new SAS variable named SASEffectDate to preserve the original variable. Once you have it as a SAS variable, you don't need to do anything else; the SAS Access product will know how to make the references to the external database.
Here is an example of doing something similar using PROC SQL:
data have; /* Just a dummy data set for illustration */
do EffectDate = 1130101,0130101;
i+1;
output;
end;
run;
proc sql;
create table want as
select t2.*
, case when t2.EffectDate < 999999 /* starts with 0 */
then input('19' || substr(put(EffectDate,z7.),2),yymmdd8.)
else input('20' || substr(put(EffectDate,z7.),2),yymmdd8.)
end as SASEffectDate format=yymmdd10.
from have t2
;
quit;