How to check a real table size in an SAP BW HANA system through M_CS_TABLES

How to check a real table size in an SAP BW HANA system

One way to get the theoretical size of a table is to multiple the number of records in SE16 (enter table name, and click on Number of entries button or CTRL-F7) by the table width from the table definition in SE11, using the menu option Extras -> Table length). This gives you a theoretical size.

But you can see the real size by querying (SQL) view M_CS_TABLES in HANA studio. This gives you information regarding the specific table such as total memory size, delta memory size, etc. If you want to know the active table size for DSO 0SD_O01 – /BI0/0SD_O0100, you execute the SQL command

SELECT * FROM "SYS"."M_CS_TABLES" 
  WHERE TABLE_NAME = '/BI0/A0SD_O0100';

If you want to know the fact table size for the Cube 0SD_C01, the SQL command would be:

SELECT * FROM "SYS"."M_CS_TABLES"
  WHERE TABLE_NAME = '/BI0/F0SD_C01';

If you want to know the top 100 tables by size:

SELECT top 100 "MEMORY_SIZE_IN_TOTAL", "TABLE_NAME" 
  FROM "SYS"."M_CS_TABLES" 
  ORDER BY "MEMORY_SIZE_IN_TOTAL" DESC

This link is for the online help for table M_CS_TABLES