thank you Philip,

I will test it today.


Greetings Manuel

Philip Semanchuk schrieb am Dienstag, 7. Juni 2022 um 17:13:28 UTC+2:

>
>
> > On Jun 7, 2022, at 5:46 AM, Trainer Go <[email protected]> wrote:
> > 
> > Hello guys,
> > 
> > Im executing 2 queries in my python program with sqlalchemy using the 
> pyodbc driver.
> > The database is a Adaptive SQL Anywhere Version 7 32 Bit.
> > 
> > When im executing the queries in a DB UI it takes 5-6 seconds for both 
> together and when im using the same queries in my python programm it takes 
> 5-6 minutes instead of 6 seconds. What im doing wrong? Im new at this.
>
> To start, debug one query at a time, not two.
>
> Second, when you test a query in your DB UI, you’re probably already 
> connected to the database. Your Python program has to make the connection — 
> that’s an extra step, and it might be slow. If you step through the Python 
> program in the debugger, you can execute one statement at a time (the 
> connection and the query) to understand how long each step takes. That will 
> help to isolate the problem.
>
> Third, keep in mind that receiving results takes time too. If your DB UI 
> is written in C or some other language that allocates memory very 
> efficiently, it might be a lot faster than building a Pandas dataframe. 
>
> You might want to eliminate Pandas entirely so you don’t have to question 
> whether or not that’s the source of your slowdown. You could do this 
> instead -
>
> for row in conn.execute(my_query).fetchall():
> pass
>
> That will force your Python program to iterate over the result set without 
> being forced to allocate memory for all the results.
>
> Hope this helps
> Philip
>
>
>
>
>
>
> > 
> > would the connection string or query help?
> > And i only selecting some datas from the db and converting it into two 
> dataframes so i dont inserting, updating or deleting datas.
> > 
> > I hope somebody can help me.
> > 
> > Best regards Manuel
> > 
> > -- 
> > SQLAlchemy - 
> > The Python SQL Toolkit and Object Relational Mapper
> > 
> > http://www.sqlalchemy.org/
> > 
> > To post example code, please provide an MCVE: Minimal, Complete, and 
> Verifiable Example. See http://stackoverflow.com/help/mcve for a full 
> description.
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> .
>
>

-- 
SQLAlchemy - 
The Python SQL Toolkit and Object Relational Mapper

http://www.sqlalchemy.org/

To post example code, please provide an MCVE: Minimal, Complete, and Verifiable 
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