Re: Basic Question about DELETE

From: Ike (rxv_at_hotmail.com)
Date: 03/17/04

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    It seems what I SHOULD do, is add a field, a boolean, a simple 'deleted'
    field. This way, referential integrity CAN be maintained, and, in an editor,
    only show those fields where deleted==false. It seems to be a solution,
    no? -Ike

    "David Harper" <devnull@obliquity.u-net.com> wrote in message
    news:_wI5c.3852$a95.3582@newsfe1-win...
    > Harald Fuchs wrote:
    > > In article <1dfad7c0.0403160319.222b72f8@posting.google.com>,
    > > devnull@obliquity.u-net.com (David Harper) writes:
    > [SNIP]
    > >>Unfortunately, MySQL doesn't yet support cascading deletes, so Ike will
    > >>have to follow Silvio's original suggestions.
    > >
    > >
    > > From the fine MySQL manual:
    > >
    > > Starting from version 3.23.50, you can also associate the `ON DELETE
    > > CASCADE' or `ON DELETE SET NULL' clause with the foreign key
    > > constraint. Corresponding `ON UPDATE' options are available starting
    > > from 4.0.8. If `ON DELETE CASCADE' is specified, and a row in the
    > > parent table is deleted, then InnoDB automatically deletes also all
    > > those rows in the child table whose foreign key values are equal to
    the
    > > referenced key value in the parent row.
    >
    > This is correct for InnoDB tables, but not for MyISAM, which is the
    > default table type. If Ike's application demands referential integrity,
    > he should make sure that he is using InnoDB tables.
    >
    > David Harper
    > Cambridge, England
    >

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