>> So, why I don't use prepare here: let's say I'm testing the worst
>> stress case :-)  Imagine you have thousands of such kind of queries -
>> you cannot prepare all of them! :-)
>
> Thousands?  Surely there'll be a dozen or three of most common queries,
> to which you pass different parameters.  You can prepare thoseu

Ok, and if each client just connect to the database, execute each kind
of query just *once* and then disconnect?..  - cost of prepare will
kill performance here if it's not reused at least 10 times within the
same session.

Well, I know, we always can do better, and even use stored procedures,
etc. etc.


>
>> Now, as you see from your explanation, the Part #2 is the most
>> dominant - so why instead to blame this query not to implement a QUERY
>> PLANNER CACHE??? - in way if any *similar* query is recognized by
>> parser we simply *reuse* the same plan?..
>
> This has been discussed in the past, but it turns out that a real
> implementation is a lot harder than it seems.

Ok. If I remember well, Oracle have it and it helps a lot, but for
sure it's not easy to implement..

Rgds,
-Dimitri

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