_.at

Ho to install SHA-1 support for PostgreSQL

last change: 2012-01-17

In the PostgreSQL source directory:
cd contrib/pgcrypto
make; make install

start psql and create a utility function:

psql -Upostgres template1

-- for Postgres < 9.1:
template1=# \i contrib/pgcrypto/pgcrypto.sql
-- for Postgres >= 9.1:
template1=# CREATE EXTENSION pgcrypto;

-- common part:
template1=# CREATE OR REPLACE FUNCTION sha1(varchar) returns text AS '
SELECT encode(digest($1::bytea, ''sha1''), ''hex'')
' LANGUAGE SQL STRICT IMMUTABLE;

Links:
How to add sha1() to PostgreSQL?
Postgres Documentation: F.20. pgcrypto

permlink: _.at: Ho to install SHA-1 support for PostgreSQL

Trivia: Adding Linux Swapspace

last change: 2011-02-13

dd if=/dev/zero of=/swapfile bs=1M count=2048
mkswap /swapfile
swapon /swapfile

Don't forget to also add the last command (swapon) to the system startup scripts (e.g. in /etc/rc.local).

permlink: _.at: Trivia: Adding Linux Swapspace

Linux Kernel increasingly inefficient

last change: 2009-09-22

I knew it...
OK, it *does* support numerous plattforms and gazillions of features (almost nobody actually uses btw.). But wouldn't it be better to make these parts optional? Micro-kernel anyone? Would of course collide with the current development model -- but maybe this would also be a good time to rethink that as well.

Links:
The Register: Linus calls Linux 'bloated and huge'

permlink: _.at: Linux Kernel increasingly inefficient

Petabytes

last change: 2009-09-03

Interesting article detailing the parts of a massive storage system at reasonable costs: 67 TB under USD 8000,-. Interesting price comparison with other storage vendors is included.

Links:
Backblaze Blog: Petabytes on a budget: How to build cheap cloud storage

permlink: _.at: Petabytes

all articles represent the sole opinion of their respective author. all content comes without any warranty for correctnes, despite due diligence.