Re: How can I modify (decrease) a column ?

The reason that it won't let you is because it is just doing the easy thing and saying I won't make it smaller unless it's empty.

create a table with the following if you aren't using 8i.

create table temp_table as select pk,column_I_want_to_change from my table;

update the table you want to change and set all rows to null (column_I_want_to_change ).

change the field.

Use the temp table to update the values back.

drop the temp table.

--
Robert Fazio, Oracle DBA
rfazio_at_home.com
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"Peter Wichert" <peter.wichert_at_gis.dew.de> wrote in message
news:8gl625$9qi$1_at_gdv106.gis.dew.de...


> Hi,

>

> I'm trying to change the layout of a table. I just want to change a

 CHAR(10)


> to CHAR(8), and ORACLE tells me to clear (empty) the table first. But I

> don't have records with longer entries than 8 chars, so why must I delete

 my


> records?

>

> It says:

>

> "column to be modified must be empty to decrease column length"

>

> Generally spoken,  is there a solution to savely change my database layout

> (shure, "compatible" changes only) without loosing my data (if I know what

> i'm doing :-)) ?

>

> Thanks for any help,

> Peter

>