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Re: [LUG] furthering the revolution: ECDL



On Sat, 9 Feb 2002, kevin bailey wrote:
we see postgres having a good future because it has had ACID compliance
built-in from the begining.

My understanding was that MySQL now provides sensible behaviour
via an alternative table type, but I do wonder how many people
understand the relevant differences in quality between
apparently competing database products.

i'll have to check this out further but i believe MYSQL was file based 
initially - and has now had record locking and transactions added on - 
which doesn't feel too good.

if you use certain table types - the it can kind of implement 
transactions, but it is a hack.

postgres is probably better for DB's where the size is in the order of 
gigabytes - whereas MYSQL is suited to small jobs and being the DB 
behind small websites.  if the web-site is running e-commerce though 
postgres would again be better,

I'd disagree :) MySQL scales very well on doing rapid selections and joins 
(i.e. generating content, etc) it scales less well for inserts ( accepting 
data, etc) and doesn't really do transactions properly.

Postgres and MySQL can combine well by having all the transactions 
(updates, etc) handled by Postgres and then Have MySQL update itself from 
Postgres when its not too busy and otherwise concentrating on pushing out 
results as quick as it can.

It should be quicker to update N records in 1 go than to update N records 
in N queries as there will be less locking and no contention / blocking.

i have to set up a postgres DB on a server soon and will be running some 
tests - i'll try to find time to set up MYSQL as well and run the same 
tests - i'll post any results/conclusions,

You'll find that MySQL isn't case sensitive and Postgres is - if your 
dirty has varying or poor capitalisation it can be a pig to clean it all. 
Also Postgres uses ' instead of " for quoting values in queries. Finally 
Postgres doesn't allow you to drop a column from a table - you have to 
create a new table without teh column with data inserted by a great big 
select - this can be a pig.

regards,
A.

-- 
<A HREF = "http://termisoc.org/~betty";> Betty @ termisoc.org </A>
"As a youngster Fred fought sea battles on the village pond using a 
complex system of signals he devised that was later adopted by the Royal 
Navy. " (this email has nothing to do with any organisation except me)




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