mysql autoincrement zero value

[Leonardo Kenji Shikida <sh...@gmail.com>]

if I try to insert an object with id=0 into a mysql table that have an
autoincrement id column, strange things happens

mysql silently inserts that object with messy values. very dangerous.

is there any workaround for this in mysql or ibatis? or will I have to
check explictly for zeroed ids and throw an exception?

[]

Kenji
_______________________
http://kenjiria.blogspot.com
http://gaitabh.blogspot.com

Re: mysql autoincrement zero value

[Leonardo Kenji Shikida <sh...@gmail.com>]

I discovered this by accident, during unit tests. I needed an expected
value and then I was inserting into it with specific values.

In fact, I was wondering if a little bit of reflection like

    public Object insert(Object o) throws SQLException{
        return this.dbclient.insert("insert"+o.getClass().getSimpleName(),o);
    }

could make my life easier. But it seems it won't be a good idea

in fact, it's worse than I thought

      1) inserting an object with id explicitly equal zero will make
         mysql create a new object with the next autoincrement value
         and will simply ignore all the other column values. Silently

      2) inserting an object with another explicitly non-zero id value
         will fail the query ibatis uses to get the next generated id
         (basically because no id was generated) and will return zero

good bye reflection :(

On 12/7/05, Larry Meadors <lm...@apache.org> wrote:
> Why are you inserting into an auto_increment field?
>
> Larry
>
>
> On 12/7/05, Leonardo Kenji Shikida <sh...@gmail.com> wrote:
> > if I try to insert an object with id=0 into a mysql table that have an
> > autoincrement id column, strange things happens
> >
> > mysql silently inserts that object with messy values. very dangerous.
> >
> > is there any workaround for this in mysql or ibatis? or will I have to
> > check explictly for zeroed ids and throw an exception?
> >
> > []
> >
> > Kenji
> > _______________________
> > http://kenjiria.blogspot.com
> > http://gaitabh.blogspot.com
> >
>


--

[]

Kenji
_______________________
http://kenjiria.blogspot.com
http://gaitabh.blogspot.com

Re: mysql autoincrement zero value

[Larry Meadors <lm...@apache.org>]

Why are you inserting into an auto_increment field?

Larry


On 12/7/05, Leonardo Kenji Shikida <sh...@gmail.com> wrote:
> if I try to insert an object with id=0 into a mysql table that have an
> autoincrement id column, strange things happens
>
> mysql silently inserts that object with messy values. very dangerous.
>
> is there any workaround for this in mysql or ibatis? or will I have to
> check explictly for zeroed ids and throw an exception?
>
> []
>
> Kenji
> _______________________
> http://kenjiria.blogspot.com
> http://gaitabh.blogspot.com
>