database - Make a column nullable in Ingres -

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i make column nullable in ingres database, couldn't find statement, or tool allow me this.

anyone can me?

ingres version: 9.2.1

so let's create table not null field:

create table test ( field_1 char(10) not null )

in order convert field allows null values need this:

alter table test alter column field_1 char(10) null

for reference actian ingres sql manual can found here: actian ingres 2006 sql reference guide


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