Main storage size and Delta storage size

[Former Member]

Hi,

Can some one help me with Main storage size and Delta storage size.

In column store table we can fine find the size of both delta and main store size. When the data is loaded into the table, the delta storage size is more and main storage size is less and after the merge command the data is moved to the main store.

Does the merge command moves the data from RAM to database.

Thanks,

Shakthi Raj.

[former_member93896 · Accepted solution]

Hello Shakthi,

everything is in RAM: Main store and delta store and the merge process are all happening in RAM. So simply speaking the merge process takes the data out of the delta memory structures and puts it into the main memory structure. All changes are of course logged in the file system (data and log files).

Regards,
Marc
SAP Customer Solution Adoption (CSA)

[Former Member · Accepted solution]

What is the default delta merge state?  Do I need to set my table to Alter table <> enable automerge; for every table?

[former_member93896 · Accepted solution]

The default is that all column tables will automatically be merged (asynchronously). Tables for SAP NetWeaver BW are an exception (automerge = off) and BW will trigger the merge when appropriate.

Regards,
Marc
SAP Strategic Customer Engagements (SCE)