Unable to fetch app definition. Error: Request can...

Vernelle_Kruse2 · 08-26-2020 11:39 AM

Hi there, I am getting this error from my app:

Unable to fetch app definition. Error: Request cancelled: took too long to process

does anyone know why this is happening? it started last week and then went away and now its back again.

I haven’t touched anything on my app since it was set.

Please help.

Thank you.

Steve

This is commonly caused by complex virtual column expressions that do a lot of processing. Has you app been slow to sync before this started?

Vernelle_Kruse2

Yes, It has been as of late. we’ve had it built this way for quite a while now, at least 2 months. and the issue only started happening last week.

Steve

Sounds like a good chance virtual column processing might be a problem, then. I advise reviewing your virtual columns and look for ways to optimize them, focusing on expressions that make use of FILTER() LOOKUP(), MAXROW(), MINROW(), and/or SELECT().

Vernelle_Kruse2

I have all of those on my virtual expressions. The issue is only happening for a small select few people that have a “WLA” in “ZONE” (Column) in “MAIN” (table) that this error happens. there are virtual columns in this MAIN reference other tables and columns, but i dont see why these would be the cause of the error, especially when it wasn’t an issue a week ago.

But maybe there is something I am overlooking?

Steve

The functions I mentioned all scan the content of tables. The amount of time they take to process is directly related to the size of the table they scan. As the table grows, the amount of time it takes to scan the table grows. If you’ve been adding data to your app, you’ve probably been increasing the mount of data to scan, and the amount of time has been growing along with it, until it reached a critical point and the system simply gave up and gave you the error.

Vernelle_Kruse2

so then are you saying my table is too large? and if that is the case, what are my options to resolving this issue?

Steve

In fact, I am not saying your tables are “too large”. I’m saying your app is probably too complex.

To quote myself:

See also:

jmacdon

This is correct and it helps me optimize my backend. I remove the virtual column having a code or expression LOOKUP(MAX..., from multiple refresh or waiting for 5mins up now its just a second.

Xuxun_huang

Hi,
I was stuck in this problem too!

I tried to delete virtual column and delete my google sheet data.

but, I can not do anything on my appsheet since it occur error all the time.
Could you please suggest way to solve this

Steve

Please contact AppSheet Support for help with this.

https://www.appsheet.com/Support/Contact