Crazy idea: Database replication / table replication for SAP system

[Former Member]

We are looking for a solution to replicate part of SAP ECC tables into another SAP ECC system, realtime & sychnorized!

A functional team is leading the solution from SAP functional point of view, such as sycn all the business orders to keep tables synchronized. I want to know the possibility on technical level.

What I know is it's almost impossible, the possible solutions are as follows:

1) DataGuard on whole DB level.

Question: Can this support serveral destinations sync, for example, database A to database B&C&D? The DB sid must be the same? Can destination DB start as readonly mode when sync? Can SAP start during sync to support ECC query/report? As I know, even after user login, some tables need to be updated...

2) Replication on table level. According to note 105047, there are some build-in replication tools:

2.1) Advanced Replication, supported

2.2) Streams, can not be used

2.4) Materialized Views, supported

2.3) Trigger, supported with Materialized Views but cannot use trigger-based real-time replication

Question: Which one can be used for replicating ream time huge SAP transaction tables? Only support Z/Y cutomized talbe or even support standard tables?

3) 3rd party replication product, such as sybase replication agent for oracle, others....

Question: Comparing with oracle build in functionality, they are better or worse?

I know this is crazy but still need your input regarding this.

Thanks

James

[Former Member]

1) DataGuard on whole DB level.
Question: Can this support serveral destinations sync, for example, database A to database B&C&D? The DB sid must be the same? Can destination DB start as readonly mode when sync? Can SAP start during sync to support ECC query/report? As I know, even after user login, some tables need to be updated...

To answer your DataGuard questions:

- Can this support serveral destinations sync, for example, database A to database B&C&D? Yes

- The DB sid must be the same? Yes

- Can destination DB start as readonly mode when sync? No

http://download.oracle.com/docs/cd/B19306_01/server.102/b14239/manage_ps.htm#i1014482

- Can SAP start during sync to support ECC query/report?

Yes, you can open the standby database read-write, then start SAP and run your queries/reports.

Afterwards you have to use flashback database to undo all changes and restart redo apply.

You can have a look at this whitepaper, it is very helpful to set up Data Guard:

http://www.oracle.com/us/solutions/sap/wp-ora4sap-dataguard11g-303811.pdf

Regards,

Mark

[Former Member]

Yes, you can open the standby database read-write, then start SAP and run your queries/reports.
Afterwards you have to use flashback database to undo all changes and restart redo apply.

My understanding is this is under physical standby mode. Flashback is not we want at current moment because we do not want to sync frequently.

Logical standby sounds good because both primary & standby can access DB at the same time. No flashback is required. What I want to know is:

• Is this stable enough?

• Is there any mechnisim to fix the change conflict issue? My understanding is both primary DB and standby client (SAP) can change the database at the same time. For example, when standby SAP start, then it will update table usr02 to record the last login information. But the primary DB will also update those information as well.

Thanks for any input.

James

[Former Member]

SAP note 105047 says: You cannot use "Logical Standby". So you could never switch from primary to standby.

If you just want to have a standby database for reporting and you don't care whether this is supported by SAP, then good luck. I don't know whether anyone already tested such a combination and could say whether it would be stable.

[former_member204746]

realtime sync between 2 ECC systems? not really. Why? because each DB are open in read/write mode.

if you are using Z programs, it is possible to read DB remotely and base your reports on them.

[Former Member]

Table replication does not work in read-only mode, I think it is still possible.

Reading remote DB is not considered as we are going to split the system to lower main SAP's workload.

Any other suggestion?

Thanks.

[former_member204746]

another possibility would be to put a trigger on these tables so that changes are replicated to the remote DB.

[Former Member]

According to note 105047, trigger based replication is not supported by SAP.

We've test Sybase table replcation (redo log based technology), it works, cool. But it only works for specified tables.

I am still looking for a DB level replication tool. It seems DatatGuard logical standby can works in this situation but this is also not support by Oracle. I also heard the experience on DG logcial standby was not so good. Is there any other 3rd party tool which we can use?

Thanks

James