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Comment: Re:The sorts of things you get (Score 1) 372

by magman (#44268919) Attached to: Ask Slashdot: Is Postgres On Par With Oracle?
> Flashback queries and flashback archives (they are really cool) Is that the same as time travel?

Nope, in Oracle you can run this query on any table to view the data it held yesterday:

select * from emp as of timestamp(sysdate-1);

>Oracle uses a statistical optimizer for execution plans in the engine. >They are working through the 2nd generation of it to handle situations where they are lots of high frequency values Here you go. Perhaps Oracle's statistics are more sophisticated: can you enlighten us?

At a first glance postgres seems to have all the important stuff in there, but I'm not sure how postgres handles the execution plans for prepared statements when you have skewed data and histograms on a column. This was a pain in oracle 10g and lower....

> Temporary table undos Don't know about this one.

Temporary tables in oracle are tables with data only available for the duration of your session. Everyone use the same table, but they only see their own data. Because there's no ACID compliance here there's very little redo/undo generation (WAL and undo)

Comment: Re:Clustering... (Score 1) 372

by magman (#44268431) Attached to: Ask Slashdot: Is Postgres On Par With Oracle?

I hate, hate, HATE always having to manually manage table spaces, data file size limitations, recompiling invalid objects, the HORRIBLE, painful, not entirely documented syntax of the tools (eg. expdp), the admin hostile tools that make the MS-DOS command-line look futuristic (sqlplus), etc. From an administrative perspective, Oracle is a nightmare in comparison to the relatively approachable and user-friendly Postgres.

When did you work with the Oracle DB? 1995? Tablespace management: use bigfile tablespaces and autoextend if you need lots of data, one datafile will go to 32TB with a normal 8k blocksize. Recompiling invalid objects... Something has invalidated them, like a drop of a dependent object or something, and there's a script to recompile for you. Syntax for expdp: expdp help=y. sqlplus does take some time to get used to, I'll give you that one.

Oracle administration is not black magic, the documentation is good and the community is really amazing. You have views where you can delve deep into why something is not performing well, and the high availability/disaster recovery solutions are really the best there is.

Comment: Re:Still does not solve much (Score 1) 632

by magman (#17126390) Attached to: Solar Cell Achieves 40% Efficiency
Electrical storage is something we won't see until we have solved our energy needs... I'm not talking about 80% of our energy from solar cells, but something like 10% would be achievable.

Nuclear power is the energy source of the near future, we need something that's CO2-free. CERN in Switzerland think they have a solution to Thorium based power plants... Now, that would be interesting.

Life in the state of nature is solitary, poor, nasty, brutish, and short. - Thomas Hobbes, Leviathan