maybe I I formulated it not precise enough.
I need to check if some instance of a model comes from some database query (e.g. via get(..)) or is instanciated 'by hand'. and not jet written to the database. In this case I don't need to know, if there is an related object (e.g. with the same pk or same values for its attributes) in the database.

bg,
Johannes

On 20.01.2014 18:21, Avraham Serour wrote:
well you have a problem then, the database is the one holding the data,
if you want to know if the data exists will would need to ask the one
responsible for it, if not the DB then who?

you could keep a copy in memory but then you will have two problems. are
you actually having problems with exists() or is this just premature
optimization?


On Mon, Jan 20, 2014 at 6:13 PM, Johannes Schneider
<johannes.schnei...@galileo-press.de
<mailto:johannes.schnei...@galileo-press.de>> wrote:

    I don't do, because I don't want do to have a query against the
    database.


    On 20.01.2014 16:25, Kelly Nicholes wrote:

        Wait-- Why aren't you using exists()?  Don't even check the pk.
          Model.query.exists() was made for this.



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