My Experience – SAP HANA: Columnar Storage vs Row Storage – Statistics on Compression
I want to know how much SAP HANA columnar storage table is efficient in terms of compression against row storage table and I have calculated these facts with my data. [I have data with 81,42,29,991 (more than 81 crores) rows and 10 columns in csv file and
memory size of the csv file is 81 GB.]
I have listed down compression statistics below for both row based and column based tables. [P.S: these facts and statistics with respect to only my data]
I have created both row table based and column based table using my data. Both the table is having 81 crore rows and 10 columns.
Row Storage Table:
Column Storage Table:
Both tables have same no of rows.
Compression:
We will check compression ratio in both row based table and column based table. [Note: Memory size of CSV file is 81 GB. Data is imported from this file ]
Row Storage Table:
Memory Size of the table is 74 GB (approx.)
Column Storage Table:
Memory Size of the table is 9.7 GB only (approx.)
Conclusion:
For my data, columnar storage compresses the data 7.6x times more than row storage. In column storage, the same set of data stored together and it gives better compression 🙂 .
Regards,
Muthu