Re: Jaw drop: JDBC will let you update rows with the wrong data type (within reason)

It wouldn't have worked before one of the last TR's to 7.2...

Now it does.

Charles

On Wed, Oct 6, 2021 at 5:19 PM Charles Wilt <[email protected]> wrote:

> Yep this, autocasting by the db...
>
> Charles
>
> On Wed, Oct 6, 2021 at 2:19 PM Niels Liisberg <nli-y1igGha7WhZnI0JKdf8LmQC/[email protected]>
> wrote:
>
>> I think it is the auto-cast in Db2 that kicks in. And why statement 3
>> fails. For that it can not cast the current object value.
>>
>>
>> ons. 6. okt. 2021 kl. 21.58 skrev David Gibbs via JAVA400-L <
>> [email protected]>:
>>
>> > Folks:
>> >
>> > I just encountered a situation where JDBC allowed me to update rows in a
>> > table where the values did not match the column definition.
>> >
>> > As long as you use the setObject method, you can set a numeric column to
>> > a string value and a character column with a numeric value.
>> >
>> > The value contents have to match the column definition, but it doesn't
>> > seem to care what the data type being passed in.
>> >
>> > For instance:
>> >
>> > You create a table as such ...
>> >
>> > create table testtab1 (
>> >    decfield decimal(8,0),
>> >    charfield char(10)
>> > )
>> >
>> > ... and then run code like this ...
>> >
>> > try (
>> >    Connection conn = DriverManager.getConnection(url, props);
>> >    PreparedStatement stmt = conn.prepareStatement("insert into
>> > dxglib/testtab1 (decfield,charfield) values(?,?)");
>> > ) {
>> >
>> >    stmt.setObject(1, 1);
>> >    stmt.setObject(2, "xyz");
>> >    stmt.executeUpdate();
>> >
>> >    stmt.setObject(1, "2");
>> >    stmt.setObject(2, 3);
>> >    stmt.executeUpdate();
>> >
>> >    stmt.setObject(1, "A");
>> >    stmt.setObject(2, 3);
>> >    stmt.executeUpdate();
>> >
>> > } catch (Exception e) {
>> >    e.printStackTrace();
>> > }
>> >
>> > .. the first two updates will work fine, but the 3rd will fail.
>> >
>> > david
>> > --
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