[aeroevan]

It's 100GB compressed. Parquet does a very good job of compressing most data so that's where the estimate of 10x (so 1TB) uncompressed was mentioned as a rule of thumb.

Parquet also supports much better access mechanisms, like being able to deserialize a single column without having to read in entire rows.

But like you mentioned, 1TB of data in a traditional database isn't that bad.

[usgroup]

... also remembering that a traditional dB will typically not store data raw. Row compression is normal and disk compression is normal . The typical column store advantage is block compression, predicate pushdown and column order storage.

[sixdimensional]

Regular databases such as SQL Server and Oracle have had columnar compression built in as an option along with the row stores for years now. I use it in SQL Server a lot and it works great.

[riku_iki]

you can run sql DB over compressed filesystem, and some DBs allow you to compress tables too

> like being able to deserialize a single column without having to read in entire rows.

and it reads filesystem's whole page anyway

[aeroevan]

Sorry for the late reply, but parquet is a columnar format so if it's big enough data, you should have multiple pages/blocks of data in a single column for a specific row group, and then be able to seek to the next row group and sequentially read the next set of blocks.