How to Copy a Timestamp Datatype - sybase

Question

I have a table with a TIMESTAMP column:
create table dbo.EX_EMPLOYEE (
NAME_X varchar(10) null,
RECORD_TIME_STAMP timestamp null
)
when I copy the rows from one table to another, using either:
SELECT * INTO EX_EMPLOYEE_T
FROM EX_EMPLOYEE
WHERE 1=0
or:
INSERT INTO EX_EMPLOYEE_T
SELECT *
FROM EX_EMPLOYEE
I get this warning:
Warning: A non-null value cannot be inserted into a TIMESTAMP column by the user. The database timestamp value has been inserted into the TIMESTAMP field instead.
The TIMESTAMP column in the target table is replaced with the current database timestamp.
My question
How to copy rows with a TIMESTAMP column, while preserving the TIMESTAMP value from the source table ?
(Is there a setting similar to SET IDENTITY ON/OFF)
My scenario
I have 2 tables, one for "live" data and the other for "backup", so I need to copy the rows with the TIMESTAMP intact. I need it intact in order to detect if there has been a change to the "live" row.

Answer 1

The Sybase (now SAP) replication server (SRS) can replicate timestamp values between Sybase/SAP ASE tables, ie, the SRS maintuser can insert explicit values into a column of type timestamp.
How is this possible? There are a few requirements:
the user performing the insert (to the timestamp column) must have the replication_role role (and it has to be active)
you need to issue the set timestamp_insert on command (NOTE: this will generate an error if your user doesn't have replication_role)
you need to explicitly list the target table's columns in the insert statement
Setup:
exec sp_displaylogin
go
...
Configured Authorization:
...
replication_role (default ON) <<<=== verify role assigned and active
...
create table EX_EMPLOYEE
(NAME_X varchar(10) NULL
,RECORD_TIME_STAMP timestamp NULL
)
go
insert into EX_EMPLOYEE (NAME_X) values ('Larry')
insert into EX_EMPLOYEE (NAME_X) values ('Mo')
insert into EX_EMPLOYEE (NAME_X) values ('Curly')
go
select * from EX_EMPLOYEE
go
NAME_X RECORD_TIME_STAMP
---------- ------------------
Larry 0x00000000ec4304fa
Mo 0x00000000ec4304fd
Curly 0x00000000ec430501
select * into EX_EMPLOYEE_T FROM EX_EMPLOYEE where 1=2
go
Now for some insert tests ...
-- haven't issued the 'set timestamp_insert on' commmand, yet
insert into EX_EMPLOYEE_T
select * from EX_EMPLOYEE
go
Warning: A non-null value cannot be inserted into a TIMESTAMP column by the user. The database timestamp value has been inserted into the TIMESTAMP field instead.
-- received the *WARNING*, ie, rows are inserted but they receive new timestamp values
select * from EX_EMPLOYEE_T
go
NAME_X RECORD_TIME_STAMP
---------- ------------------
Larry 0x00000000ec430548 <<<=== different from what's in EX_EMPLOYEE
Mo 0x00000000ec43054a <<<=== different from what's in EX_EMPLOYEE
Curly 0x00000000ec43054c <<<=== different from what's in EX_EMPLOYEE
-- enable direct insert of timestamp values
set timestamp_insert on
go
truncate table EX_EMPLOYEE_T
go
-- w/out explicitly listing target columns ...
insert into EX_EMPLOYEE_T
select * from EX_EMPLOYEE
go
-- no warning message is generated, insert succeeds, but new timestamp values are generated
select * from EX_EMPLOYEE_T
go
NAME_X RECORD_TIME_STAMP
---------- ------------------
Larry 0x00000000ec430555 <<<=== different from what's in EX_EMPLOYEE
Mo 0x00000000ec430557 <<<=== different from what's in EX_EMPLOYEE
Curly 0x00000000ec430559 <<<=== different from what's in EX_EMPLOYEE
truncate table EX_EMPLOYEE_T
go
-- this time we'll explicitly list the target table's columns ...
insert into EX_EMPLOYEE_T (NAME_X, RECORD_TIME_STAMP)
select * from EX_EMPLOYEE
go
-- and now we see the timestamp values copied from the source
select * from EX_EMPLOYEE_T
go
NAME_X RECORD_TIME_STAMP
---------- ------------------
Larry 0x00000000ec4304fa <<<=== same as what's in EX_EMPLOYEE
Mo 0x00000000ec4304fd <<<=== same as what's in EX_EMPLOYEE
Curly 0x00000000ec430501 <<<=== same as what's in EX_EMPLOYEE
Above was tested on a ASE 15.7 SP138 dataserver.