Обсуждение: NULL values

On Tue, Jul 10, 2001 at 09:40:31AM +0100, Mark Muffett wrote:
> Is there a Postgresql equivalent to the Oracle NVL( ) function,
> which allows a SELECT statement to fill in default values if a
> column is NULL?

Yes.

Use the DEFAULT keyword while creating the table.

That is:

    CREATE TABLE account (
    name    CHAR(20),
    balance    NUMERIC(16,2) DEFAULT 0,
    active    CHAR(2) DEFAULT 'Y',
    created TIMESTAMP DEFAULT CURRENT_TIMESTAMP
    );

Then :

    INSERT INTO account (name)
    VALUES ('Federated Builders');

will leave the inserted rows with no nulls, but the balance will be
zero, and the "created" field will have the date/time of the insert.

> Mark Muffett

         -crl
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Chad R. Larson (CRL22)    chad@eldocomp.com
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