Re: what's the impact of this

If it is a very large and very busy table you'd best think twice. Every row in the table will be updated. See example below.

SQL> desc g1

 Name                            Null?    Type
 ------------------------------- -------- ----
 ID                              NOT NULL NUMBER
 VAL                                      NUMBER
 LASTCHANGE                               DATE

SQL> select * from g1;

        ID VAL LASTCHANGE
---------- ---------- -----------

         1          4
         2          5

SQL> alter table g1 add(test number default 5);

Table altered.

SQL> select * from g1;

        ID VAL LASTCHANGE TEST ---------- ---------- ----------- ----------

         1          4                      5
         2          5                      5

SQL> desc g1
 Name                            Null?    Type
 ------------------------------- -------- ----
 ID                              NOT NULL NUMBER
 VAL                                      NUMBER
 LASTCHANGE                               DATE
 TEST                                     NUMBER

Gene Hubert
Durham, NC

blah_at_blah.com (blah) wrote in message news:<9m4m0s$8uc1_at_inetbws1.citec.com.au>...
> Hi All,
>
> Could someone discribe the possible impact/impacts of running this sql against
> a busy production database.
>
> alter table customer
> add(deleted varchar2(1) default 'N');
>
> Thanks,
> Chris
Received on Fri Aug 24 2001 - 07:04:08 CDT