Relationship betwwen livecache/maxdb and oracle database

[Former Member]

Dear SAP experts,

I have a question about livecache.

My system is: SPP+Oracle+Livecache, and when I stop the system, I follow the step: stop livecache, stop oracle database, stop spp.

I do not know the relationship between livecache and oracledata:

1. The livecache is a complete database? The oracle database is useless?

2. In the normal progress, SPP communicate with livecache and oracle database?

3. The data in livecache and the oracle database is synchronized?

Thanks

Best Regards

Shuai.zhongwei

[Former Member · Accepted solution]

hi Zhongwei,

SAP liveCache technology is an object-based enhancement of the MaxDB database system and was developed to manage complex objects (e.g. in logistical solutions such as SAP SCM/APO)

In solutions of this type, large volumes of data must be permanently available and modifiable. You can use SAP liveCache technology to represent data structures and data flows (such as networks and relationships) more easily and effectively.

And normally in SCN, SCM, APO system Oracle DB is used as a baseline DB which stores all data. And livecache store and calculates the real-time data based on DTP,SNP, heuristics So size of the livecache data is lesser as compared to Oracle DB.

For your 3 questions below ans can be given:-

1. The livecache is a complete database? The oracle database is useless?

Livecache is a complete DB and is based on SAP MAXDB and you can perform all DB operations on it.

Oracle DB is not useless as explained earlier.

2. In the normal progress, SPP communicate with livecache and oracle database?

Yes it does communicate with Livecache and Oracle based on the type of jobs and process chains and optimizations tranasctions its running.

3. The data in livecache and the oracle database is synchronized?

Yes it is.

Let us know if this has resolved your query.

Regards,

Ram

[Former Member · Accepted solution]

Hi Ram,

Your answer is so helpful.

And then, if the data in livecache and the oracle database is synchronized, HOW can I backup and restore the data to keep the synchronization? Is it ok for ONLY backuping/restoring oracle and backuping/restoring livecache independently?

PS: I only find "How to backup oracle" and "How to backup livecache/maxdb", but I have not found the information of "How to backup oracle+livecache".

Thanks very much.

Best Regards.

Shuai.zhongwei

[Former Member · Accepted solution]

hi shuai,

There is no combine oracle+livecache backup/restore guides as i know and never came across one.

so you have to do the backup restore of oracle & livecache independently. And for the data synchronization part you can do a point in time recovery.

Let me know if this helped.

Regards,

Ram

[former_member229109 · Accepted solution]

Hello,

1. The livecache is a complete database? The oracle database is useless?

- If you installed the SCM application server on Oracle database, you run the SCM on the Oracle database.

  Some SCM componects like APO need the liveCache database to run the applications.

The APO master data saved in SCM database and in liveCache. The APO transactional data < orders, TS data ... > are available only in liveCache on SCM system. In liveCache the objects stored in the class containers and can be accessed and manipulated only via LCA routines, for speed up the liveCache data loaded to memory for access . The registration of the LCA routines is done automatically when the liveCache on MAXDB is started in LC10, check the lcinit.log file.                    

The shared procedures in the LiveCache are written in C++  and shipped to the customers as binary shared libraries (LCAPPS-Routines) together with the LiveCache on MAXDB.

Names of all prosedures, which have been called from ABAP, you can find executing 'lc10'             

transaction on your SAP SCM system.                                                               

If you need to see the interfaces of the procedures, the LCA routines called in '/SAPAPO/OM' functions from ABAP, you may use 'se80' transaction and navigate in the Development class          

'/SAPAPO/OM'.   

See more details at

service.sap.com/scm  

-> SAP SCM in DEtail ->TECHNOLOGY

"liveCache Overview"

2. In the normal progress, SPP communicate with livecache and oracle database?

- SPP (Service Parts Planning) is part of APO functionalities as DP or SNP on SCM system.

   To run the SPP functionalities you need install the SCM application server and liveCache database.

    If you install the SCM system on Oracle DB, you need the Oracle DB to run the appl. SCM system.

    The applications will call the //om* functions, which called the LCa routiens to access the liveCache data and munipulate them, when it will be needed. It's dependednt on the application scenario & data, which you have.

3. The data in livecache and the oracle database is synchronized?

- On the SCM system the data should be consistent beetween liveCache, SCM Database and connected R/3 system.

Before the SCM application transaction committed successfully the data will be updated in liveCache, SCM DB and in connected R/3 system < if it needed > in sync.

Review the SAP note:

1723242 - SCM/APO and ERP consistency after liveCache recovery

Regards, Natalia Khlopina

[luisdarui]

Hi Zhongwei,

While liveCache is related to MaxDB (it can also run on HANA), you should seek help with this content in the following SCN space:

For your questions, I don't know what SPP stands for, but:

1) Yes, liveCache is a database and no, Oracle isn't useless in this scenario as the APO/SCM database runs on it. You need both databases (it can also run on HANA, MaxDB, SQL Server, DB2, ASE).

2) Can't answer as I don't know what is SPP in the MaxDB context

3) Yes, they're synchronized and if you have any inconsistency you might face errors during simulations, etc.

Regards,

Luis Darui

[Former Member]

Hi Darui，

Thanks for your answer, it is helpful for me.

And you said  "3) Yes, they're synchronized and if you have any inconsistency you might face errors during simulations, etc."

Then:

1) How to backup the data? As I know Oracle hold the whole data, so we only need to backup oracle and not need to backup livecache?

2) If I need to backup Oracle and Livecache independently,  How can I keep the inconsistency when recover data? 

Could you share your experience ?

Thanks very much.

Best Regards

Shuai.zhongwei

[Former Member]

Hi Shuai,

Below are the comments from my end.

And you said  "3) Yes, they're synchronized and if you have any inconsistency you might face errors during simulations, etc."

--> You can correct those inconsistencies in data. In case of  APO/SCM system we use /sapapo/om17 & om13 t codes to correct those inconsistencies

Then:

1) How to backup the data? As I know Oracle hold the whole data, so we only need to backup oracle and not need to backup livecache?

--> Yes oracle does have whole data, but you need to backup both Oracle as well as livecache in order to have a complete live system without any data issues.

2) If I need to backup Oracle and Livecache independently,  How can I keep the inconsistency when recover data?

--> the answer in given in reply of 3. And mostly the inconsistencies are related to update which is normally taken care by the Functional teams. Also one need to have a con-current backups defined. The backup statergy has to be like 1st Oracle backup and then livecache or both simultaneously. so that you get a point in time recovery done. or a offline backup during same time windows this will reduce your most issue related to data.

Also to be noted both Oracle/Livecache backup happening at same time affects system performance.

Let us know if you need more inputs on same.

Regards,

Ram

[Former Member]

Luis and Ram both help me, I can not distingwish whose answer is more helpful, so according to my first phase of question, I marked the answer tensely.

Thanks both of you.