lab_10.md

Lab 10

Goals:

• Think through data loading for different data sources
• Ensure your app is performant

---

Work in your Project team.

---

All data in BigQuery

Use BigQuery for all your datasets. For each data source:

1. What type of data loading will you use? Why? Explain as Markdown in your repository.
2. Repeat the middle steps from Part 5.

---

Performance

Ensure each page of your app (if there are multiple) fully loads within two seconds.

• Display the overall page load time using:

  import time
  import streamlit as st
  
  start_time = time.time()
  
  # --- your page code here ---
  
  elapsed = time.time() - start_time
  st.caption(f"Page loaded in {elapsed:.2f} seconds")

• You can use caching in Streamlit, but don't rely on that exclusively.

• Timing Function[s] in Python can help you identify where the slowdown(s) are.

Hint

You may need to push logic/filtering from pandas to SQL to reduce the number of records that need to be loaded from the database by your app.

---

Record

Make a screen recording starting your app locally, then loading each page in real time. Some options for recording:

• Mac
• Windows
• Zoom

---

Submit

Submit via CourseWorks:

• Links to the pull request(s)
• The screen recording