space taken by a row & compressed data

Leonardo Francalanci wrote:

With mysql I know how much space a row will take, based on the datatype
of it columns. I also (approximately) know the size of indexes.
Is there a way to know that in postgresql?

We have an FAQ item about this.

Is there a way to pack (compress) data, as with myisampack for mysql?

Long data values are automatically compressed.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073

Hi Leonardo,

Am Do, den 26.08.2004 schrieb Leonardo Francalanci um 15:51:

With mysql I know how much space a row will take, based on the datatype
of it columns. I also (approximately) know the size of indexes.
Is there a way to know that in postgresql?

Is there a way to pack (compress) data, as with myisampack for mysql?

in the contrib dir you will find something (dbsize or so)
to check for sizes of objects (at least tables)

Due to the MVCC you happen to have multiple versions
of an updated row at the same time so the numbers arent
very exact all the time.

Large objects such as text columns are stored in compressed
form already.

HTH
Tino Wildenhain