Speeding up sync times, virtual columns recalculated for every table stored in external database

AppSheet AppSheet Q&A
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Hello, I am experimenting with an external database to reduce sync times. Looking at the monitoring logs shows that despite no changes being made to the app’s data, pressing sync causes virtual columns for every table to recalculate. This adds quite a bit of extra time to the syncing:

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This happens despite delta syncing and caching being enabled (does delta syncing affect virtual columns?). Is it normal for virtual columns to be recalculated for all tables despite no changes being made?

On the other hand, my identical copy of the app that uses google sheets to store data will not recalculate virtual columns upon syncing.

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I would appreciate any advice and resources regarding this.

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Yes VCs recalculate on every sync

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Your “identical copy” has no data:

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No rows mean no virtual columns means nothing to compute. Of course performance is different.

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The external database copy was clone from the “identical copy”, it definitely contains data as shown above. I assumed that the 0 rows read log was due to delta sync, where there was no rows to read since nothing was changed. let me know if otherwise.

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I have no experience with delta sync since I’ve never worked on an app that didn’t need virtual columns updated.

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I believe delta sync works off of the modification timestamp of a gsheet, and so doesn’t do anything for any other sources of data.

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