Re: Dropping fields from table description ?

In article <2kj3tq$iqm_at_reznor.larc.nasa.gov>, jka_at_air77.larc.nasa.gov (J. Keith Alston) wrote:

> Hi,
> Does anyone know if there is a way to drop a field from a table description in
> Oracle 6 on a VAX? All of the references that I have show you how to modify a
> field or add a field but not how to drop a field. Any help would be greatly appreciated.

It is not possible to drop or shrink a column (other than some hacks in the data dictionary as user sys so you can easily destroy your hole database, and chances are good you will). Workaroud is: create a new table with the columns you want from the old table, then drop the old table and rename the new table to the name of the old one.

SQL> create table new_table as (
  1> select column1, column3, substr(column4,1 15) column4
  2> from old_table );

table created.
SQL> drop table old_table;

table dropped.
SQL> rename new_table to old_table ;

Remeber, with the "drop table" command you will loose all the indexes, grants etc. on the table so check it before  

> Thank you.

 You're welcome
>
> =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=
> Keith Alston Lockheed Eng & Sci Co + There's a less than 5% chance of
> MS 130 Nasa LaRC Hampton VA 23666 = tonight and tomorrow
> jka_at_air77.larc.nasa.gov +
 

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