Add a New Column Before An Existing Column in 10g.

Question

Hi all,
I Want to add column in a table ,before an existing column in Oracle 10G database.
table A:
id number,
name varchar,
job varchar,
status char.
i want to add a column before "JOB".
I.E) USING AFTER OR BEFORE IN ALTER TABLE SYNTAX.

Answer 1

887268 wrote:
Hi all,
I Want to add column in a table ,before an existing column in Oracle 10G database.
table A:
id number,
name varchar,
job varchar,
status char.
i want to add a column before "JOB".
I.E) USING AFTER OR BEFORE IN ALTER TABLE SYNTAX.There's no such option, and to be honest there's no real need to do it as Oracle doesn't care what order the columns are in, and you can select out the columns in your queries in whatever order you want. You could use the DBMS_REDEFINITION package (http://docs.oracle.com/cd/B19306_01/appdev.102/b14258/d_redefi.htm) but unless you're really struggling then that's perhaps a little bit over the top. The simplest way if you really feel you need to do it is to create a new table based on the existing one with your new column in it and selecting the data into it at the same time...
create newtable as
select id, name, cast(null as varchar2(10)) as newcolumn, job, status from tableA;and then drop the original table and rename the new one...
drop table tableA;
rename newtable to tableA;of course you would need to recreate any constraints, indexes, triggers etc., and it could be problematic if you have foreign keys etc. but you have to weigh up what you are wanting to do and why you really need to put a new column in the middle of other columns rather than just putting it on the end.