DB LINK Oracle to SQL Server SQL Server TimeStamp converts to Oracle Date

Question

Hi All,
I have created a DB link between Oracle 10g 10.2.0.5 to SQL server 2005 using Oracle 11g gateway. When I execute a query from Oracle that selects data from SQL server using the DBLINK then the column value of type Timestamp from SQL server gets converted to Date data type in Oracle and it losses the time value.
Is there some way (in gateway configurations or in select query sql ) that the SQL server data type Timestamp gets converted to Oracle's Timestamp?
Please help.
Best Regards!
Irfan
Edited by: irf_mas on Mar 13, 2012 3:23 AM

Answer 1

You're getting the ORA-2070 error as the gateway that you are using is not supporting the to_timestamp function in this context. You need to rewrite the code.
Best would be if you first check out the data format that is sent as a string when you just select the date column - for example:
data_create_dt
Jan 11 2012 1:40PM
Now the easiest way is to make sure the format you are using in your where clause matches the string from the SQL Server:
select * from "data_ms_view"@FREETDS_DG4ODBC_EMGTW_11_2_0_3 where "data_create_dt"<'Jan 11 2012 1:41PM';
which will result in:
data_create_dt
Jan 11 2012 1:40PM
BTW,
it works with all formats the SQL Server understands:
SQL> select * from "data_ms_view"@FREETDS_DG4ODBC_EMGTW_11_2_0_3 where "data_create_dt">'11-JAN-12 01.40.00.000000000 AM';
data_create_dt
Jan 11 2012 1:40PM
Another way using binds:
SQL> variable datum varchar2(26);
SQL> exec select to_char(systimestamp,'MON dd yyyy hh:mi') into :datum from dual;
PL/SQL procedure successfully completed.
SQL> print datum
DATUM
MAR 19 2012 08:29
SQL> select * from "data_ms_view"@FREETDS_DG4ODBC_EMGTW_11_2_0_3 where "data_create_dt" <:datum;
data_create_dt
Jan 11 2012 1:40PM
There are several ways to get a result, just make sure you don't use an unsupported function in your statement. A list of supported functions is found in the manual.