how many 1sts of any month were sundays – since 1901-01-01?

nixternal wrote about boost library for c++.

with it he was able to find the answer to title question in miliseconds (he didn't specify how many, but let's assume that is was less than 10 ms).

so i decided to check how fast can i do it in postgresql …

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shared buffers and their impact on performance

just lately we found interesting case about shared_buffers settings.

the database in question is rather simple:

  • 3 tables
  • a bit over 60 gigabytes
  • around 150 million rows

the server we run it on is not really fancy:

  • 2, single core, 3ghz xeons
  • 16 gb of ram
  • 6x 72gb, scsi, 15krpm discs in low-end hardware raid 10.

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overprotective developers

i'm recently under impression that pg developers are overprotective. who do they protect?

us, users.

i mean – don't get me wrong – i live with, and (to some extent) thanks to the piece of marvelous technology which is postgresql ordbms.

i use it, i try to help other use it. i don't think there is any better database available now (at the very least – for my purposes).

but, just lately, i some to see some cases where decissions are made in a way to “protect us (dbas) from our faults".

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encrypted passwords in database

in most applications you have some variant of this table:

CREATE TABLE users (
    id serial PRIMARY KEY,
    username TEXT NOT NULL,
    passwd TEXT
);

and, usually, the passwd stores user password in clear text way.

this is usually not a problem, but in case you'd like to add password encryption in database, there are some ways to do it – and i'll show you which way i like most.

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