Reading data quickly

Using Streamlit
1

Hi,

I’ve made a few streamlit apps now and it’s gone well. But I was wondering how I could read data quicker than I am currently doing. Typically what i do is the user enters some inputs (via some selections) in the left pane, and using this information i read a particular dataframe or set of dataframes that is then cached into the main page. Sometimes I use json files instead of dataframes as well.

is there a better way to do this? I usually also have this kind of setup where the user chooses what data to be shown, then waits for it before playing around with it.

2

Hi @tbrown,

Welcome to the Streamlit community. What you’re doing sounds fine, and is a common model with Streamlit. What specifically are you unhappy about the way you’re doing things or what do you want improved upon?

Dinesh

3

One thing i had an issue with is if i have multiple selections (inputs) that the user must choose before loading the right data, then as soon as the user clicks one, streamlit retries to load the data. But really i want streamlit to wait until the user has updated all of them.

Should I create a “submit” button where the data is not fetched until this button is clicked? Is this the best way? If so, can someone point to a quick example?

4

A couple of things for performance unrelated to Streamlit:

  • Make sure the datasets only contain the columns that are needed for the app. To paraphrase a popular coding statement, the fastest data load is one that never happens
  • Consider using a binary format instead of CSV/text files. Using something like Parquet or Arrow tables will allow you to keep the data stored in a format that’s much faster to read
  • Consider using a lightweight database like SQLite, for the same reason as using Arrow or Parquet. Databases are optimized for fast retrieval and computation.
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5

Yes, creating a submit button is best for such a situation. Will you need to maintain state, meaning is it a multi-page app or for whatever reason do you plan to use the SessionState code? If so, I find checkbox a bit more predictable and easy than the button widget.

Dinesh

1 Like
6

Thanks for the advice. I am not sure what you mean by “sessionstate code”. Do you have an example that demonstrates how a checkbox would be different in this situation?

7

I may have needlessly complicated matters/confused you with my session state remark. You can see what I mean with this thread: Programmable State Survey!

If you don’t know or care about session state, a button is perfectly fine. You can always change later if need be.

Dinesh

1 Like