[PyQt] QSqlQuery: one parameter in two different places?

[Hans-Peter Jansen]

Am Dienstag, 1. Januar 2008 schrieb Sibylle Koczian:
> Hello,
>
> my SQL query has this form:
>
> sqltext = 'UPDATE mytable SET field_1 = :newvalue WHERE field_2 <
> :newvalue'
>
> The database is SQLITE. If I use this query as is:
>
> query = QSqlQuery()
> query.prepare(sqltext)
> query.bindValue(':newvalue', QVariant(mynewvalue))
> query.exec()
>
> then nothing is updated. If I change to
>
> sqltext = 'UPDATE mytable SET field_1 = :value_1 WHERE field_2 <
> :value_2' query = QSqlQuery()
> query.prepare(sqltext)
> query.bindValue(':value_1', QVariant(mynewvalue))
> query.bindValue(':value_2', QVariant(mynewvalue))
> query.exec()
>
> the update works as expected. Can't I use the same parameter name in two
> different places of the query, if I want to use the same value twice?

On debugging such problems, I found QSqlQuery.lastQuery() pretty useful 
(before digging in the Qt source..). Hopefully it still exists in Qt4.
Applied to your problem, let us know about the outcome.

Cheers,
Pete