Re: Check Contraint Question

Justis Durkee wrote:

> One way to accomplish this requirement is to create a unique index on
> column1 and column2, so column1 will only be indexed if column 2 = 1.
>
> SQL> create table t(
> 2 column1 varchar2(32),
> 3 column2 number constraint check_column2 check( column2 in (0,1) )
> 4 );
>
> Table created.
>
> SQL> create unique index t_unique on t( decode( column2, 1, column1,
> null ) );

This does it, thank you very much.

--
Lyndon Tiu
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http://www.freelists.org/webpage/oracle-l