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So this is a good question - the answer is that you're comparing apples to oranges. This is all about in-situ data processing, which basically means that you ca

So this is a good question - the answer is that you're comparing apples to oranges. This is all about in-situ data processing, which basically means that you can run reasonably efficient, optimized queries on just regular old files that you have lying around, without having to do anything special. This is as opposed to a situation where you've spent a ton of time, effort and expense actually ingesting the data into whatever data system you're running (in this case redshift). So it's usually said that these systems are good for ad-hoc queries, i.e. one-off queries on files and datasets that you want to explore more, but it doesn't make sense to invest the hours upon hours of waiting and storage / cpu resources to bring them into your database just to make a few queries.

jnordwick 10y ago
So these ingested files are JSON or something semi-structured? I saw how the table was created, so maybe is was doing the schema-less key-value pair thing on table creation and running queries against that? I'm sure this is all in the docs somewhere, but while I have a lot of big db experience, I have about 2 hours of AWS.
- sunsu 10y ago
  The files are anything separated by line. Log files, CSV exports, anything. No specific format required.
  - jnordwick 10y ago
    So this is like a distributed awk, reparsing on every query?
- makmanalp 10y ago
  So in this example the image says "lineitem_1t_parq" which makes me think that's probably parquet files (optimized and perhaps compressed columnar file format). But it does the same stuff with CSVs too, perhaps a bit less efficiently. JSON is also definitely possible, but a bit more tricky because of the inherently nested structure and more complex format. Take a look at this for the details on a similar idea: http://stratos.seas.harvard.edu/files/stratos/files/nodb-cacm.pdf http://stratos.seas.harvard.edu/files/stratos/files/nodb-cac...
  - kakoni 10y ago
    That paper discusses PostgresRAW, which can be found here; https://github.com/HBPMedical/PostgresRAW https://github.com/HBPMedical/PostgresRAW I wonder if there are any similar projects using psql as an engine?
    - makmanalp 10y ago
      I think it's pretty common - it's open source, nice and modular codebase, reasonably advanced execution engine with stuff like MVCC. But also redshift itself, citus, hadapt and greenplum are examples that come to my mind.

jnordwick 10y ago

So these ingested files are JSON or something semi-structured? I saw how the table was created, so maybe is was doing the schema-less key-value pair thing on table creation and running queries against that? I'm sure this is all in the docs somewhere, but while I have a lot of big db experience, I have about 2 hours of AWS.

sunsu 10y ago
The files are anything separated by line. Log files, CSV exports, anything. No specific format required.
- jnordwick 10y ago
  So this is like a distributed awk, reparsing on every query?
makmanalp 10y ago
So in this example the image says "lineitem_1t_parq" which makes me think that's probably parquet files (optimized and perhaps compressed columnar file format). But it does the same stuff with CSVs too, perhaps a bit less efficiently. JSON is also definitely possible, but a bit more tricky because of the inherently nested structure and more complex format. Take a look at this for the details on a similar idea: http://stratos.seas.harvard.edu/files/stratos/files/nodb-cacm.pdf http://stratos.seas.harvard.edu/files/stratos/files/nodb-cac...
- kakoni 10y ago
  That paper discusses PostgresRAW, which can be found here; https://github.com/HBPMedical/PostgresRAW https://github.com/HBPMedical/PostgresRAW I wonder if there are any similar projects using psql as an engine?
  - makmanalp 10y ago
    I think it's pretty common - it's open source, nice and modular codebase, reasonably advanced execution engine with stuff like MVCC. But also redshift itself, citus, hadapt and greenplum are examples that come to my mind.