[ILUG] Database question...

[David Pintor]

Hi Braun,

You need to do an update (not an insert), but you can only use one value
per statement as you're targeting only one column.

If you need to update many rows with different values you need to use
conditions, depending on your needs. Something like:

update my_table set item_amount_minimum_value = 10 where id < 100
update my_table set item_amount_minimum_value = 20 where id = 200
update my_table set item_amount_minimum_value = 30 where item_name like
'%bla%'
etc...

Hope this helps.

David







On 17 December 2012 11:56, Braun Brelin <bbrelin at gmail.com> wrote:

> Hi all,
>
> I've been searching on google and asking questions in forums with no real
> result, so I figured I'd try here:
>
>
> I'm using a postgres 9.1 database on Ubuntu Linux 12.04
>
> I have a table that looks like this:
>
> id serial primary key not null
> item_name varchar (40)
> item_amount integer
>
> I then want to add a new colum via alter table which is also an integer,
> such as item_amount_minimum_value
>
> Assuming that I already have data in the table for the other three columns,
> how can I populate the new column with data?
>
> I've tried doing this:  update my_table set item_amount_minimum_value =
> (10,5,2,10,20)
> but this fails as postgres thinks that the values are a row record and not
> a list of integers.
>
> I supposed I could do something like this:  insert into my_table
> (item_amount_minimum_value) values (10),(5),(2), however is it possible to
> do this with an update rather than an insert?
>
> Thanks,
>
> Braun Brelin
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