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“Big data” features coming in PostgreSQL 9.5

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Re: “Big data” features coming in PostgreSQL 9.5

#7
post #5

I should really learn some PG and move away from MySQL. But at 40 years old i have a problem learning how to sit properly. sigh

Syntax-wise, Postgres is not much different from MySQL. You just have to learn how to use window functions which takes a bit.

Re: “Big data” features coming in PostgreSQL 9.5

#8
I would love to go back to relational, but I can't get over the linear scaling and HA ease of Cassandra and I'm willing to write my applications to work around the data model limitations. Is there any open source SQL database (i.e. "newsql") that can linearly scale with Cassandra's ease right now? I look forward to CockroachDB but it isn't done yet.

Re: “Big data” features coming in PostgreSQL 9.5

#9
So, reading between the lines, the SYSTEM TABLESAMPLE algorithm appears to be biased toward small values (in bytes, or whatever the on-disk encoding of Postgres values is).

If you choose random data pages (of fixed size), then it can fit more rows of small size than of big size.

"In the query above, SYSTEM is the name of the chosen sampling algorithm. The SYSTEM algorithm chooses a set of pseudo-random data pages, and then returns all rows on those pages, and has the advantage in running in constant time regardless of the size of the table. PostgreSQL 9.5 will also ship with the BERNOULLI sampling method, which is more rigorously random, but will take longer the larger the table is."

Re: “Big data” features coming in PostgreSQL 9.5

#10
I love PG, and don't plan to ever move away from it.

But I'm starting to wish they had in-place upgrades. Application I develop is getting to the point of "too large to make a copy of the whole db whenever I want to upgrade Postgres".

I can postpone things for a little while by replacing all our large objects with a external file storage -- but the tables themselves are growing quickly.

That'd be my favorite "big data" feature.

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