Getting started with Streamlit in Snowflake¶

Privileges required to create a Streamlit app¶

Streamlit apps are schema-level objects.

To create and edit a Streamlit app by using Streamlit in Snowflake, you must use a role that has either the OWNERSHIP privilege on the schema, or both of the following privileges:

• Granted on the database that contains the Streamlit app:

  • USAGE

• Granted on the schema that contains the Streamlit app:

  • USAGE

  • CREATE STREAMLIT

  • CREATE STAGE

You must also have the USAGE privilege on the warehouse used to run the Streamlit app.

Use the GRANT <privileges> command to grant these privileges to a role, as shown in the following examples:

GRANT USAGE ON SCHEMA streamlit_db.streamlit_schema TO ROLE streamlit_creator;
GRANT USAGE ON DATABASE streamlit_db TO ROLE streamlit_creator;
GRANT USAGE ON WAREHOUSE streamlit_wh TO ROLE streamlit_creator;
GRANT CREATE STREAMLIT ON SCHEMA streamlit_db.streamlit_schema TO ROLE streamlit_creator;
GRANT CREATE STAGE ON SCHEMA streamlit_db.streamlit_schema TO ROLE streamlit_creator;

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If a future grant is defined on database or schema, ensure that the user creates the Streamlit app using the role defined in the future grant.

Privileges required to view a Streamlit app¶

To view a Streamlit app, you must have a Snowflake account and be signed in. Additionally, you must use a role that is granted the USAGE privilege on the following:

• The database that contains the Streamlit app.

• The schema that contains the Streamlit app.

• The Streamlit app.

In most cases, when the app owner shares a Streamlit app with another role, the USAGE privilege is automatically granted to the new role. However, if a Streamlit app is created in a schema with MANAGED ACCESS, the USAGE privilege must be manually granted to the new role.

The schema owner or a user with the role with the MANAGE GRANTS privilege must grant the USAGE privilege using the GRANT <privileges> command as shown in the following examples:

GRANT USAGE ON DATABASE streamlit_db TO ROLE streamlit_role;
GRANT USAGE ON SCHEMA streamlit_db.streamlit_schema TO ROLE streamlit_role;
GRANT USAGE ON STREAMLIT streamlit_db.streamlit_schema.streamlit_app TO ROLE streamlit_role;

Select the Streamlit library version¶

For each Streamlit in Snowflake app, you can select the Streamlit library version in Snowsight or pin the version in the app’s environment.yml file. If you do not pin the version, the latest available version is used.

Snowflake recommends pinning a version of Streamlit to prevent the app from getting upgraded when a new version of Streamlit becomes available in the Snowflake Anaconda Channel.

Use smaller warehouses¶

When you run a Streamlit app in Streamlit in Snowflake you should select the smallest warehouse possible.

When running, a warehouse maintains a cache of the Python packages used by a Streamlit app. Caching Python packages improves the performance for later app loads by using the cached version of a package instead of downloading the packages again. The cache is removed when the warehouse is suspended, which may result in a slower loading of the app initially after the warehouse is resumed. As the resumed warehouse runs and runs more apps, the package cache is rebuilt, and apps that are able to take advantage of the cache will experience improved app loading performance.

Note that per-second credit billing and auto-suspend provide flexibility to start with smaller warehouses, then adjust the size of the warehouse to match the workload of the Streamlit app. You can increase the size of a warehouse at any time. See Change the warehouse of a Streamlit app for more information.

Use dedicated warehouses¶

When you use Streamlit in Snowflake, Snowflake recommends using a dedicated warehouses for running Streamlit apps. This enables you to isolate the costs of running a Streamlit apps. A dedicated warehouse may also improve the load time of the app since the warehouse does not have to manage other workloads.

See Warehouse considerations for more information.

Use a separate warehouse to run queries¶

Streamlit apps use a virtual warehouse to run the app and its queries. More advanced apps and use cases might involve running a complex query, which requires a larger warehouse.

Streamlit in Snowflake supports the USE WAREHOUSE command which specifies a current warehouse for the session. This way, you can run the app using an X-Small warehouse and complex queries using a larger warehouse.

You can use a separate warehouse to run queries in a Streamlit app as follows:

import streamlit as st
from snowflake.snowpark.context import get_active_session

# Get the current credentials
session = get_active_session()

warehouse_sql = f"USE WAREHOUSE LARGE_WH"
session.sql(warehouse_sql).collect()

# Execute the SQL using a different warehouse
sql = """SELECT * from MY_DB.INFORMATION_SCHEMA.PACKAGES limit 100"""
session.sql(sql).collect()

Access Snowflake data in your Streamlit in Snowflake app¶

In this section, you will edit the Streamlit app you just created to access data from a Snowflake table.

1. Create a BUG_REPORT_DATA table in your database and schema:

   CREATE OR REPLACE TABLE <your_database>.<your_schema>.BUG_REPORT_DATA (
     AUTHOR VARCHAR(25),
     BUG_TYPE VARCHAR(25),
     COMMENT VARCHAR(100),
     DATE DATE,
     BUG_SEVERITY NUMBER(38,0)
   );
   

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2. Add sample data into the BUG_REPORT_DATA table:

   INSERT INTO <your_database>.<your_schema>.BUG_REPORT_DATA (AUTHOR, BUG_TYPE, COMMENT, DATE, BUG_SEVERITY)
   VALUES
   ('John Doe', 'UI', 'The button is not aligned properly', '2024-03-01', 3),
   ('Aisha Patel', 'Performance', 'Page load time is too long', '2024-03-02', 5),
   ('Bob Johnson', 'Functionality', 'Unable to submit the form', '2024-03-03', 4),
   ('Sophia Kim', 'Security', 'SQL injection vulnerability found', '2024-03-04', 8),
   ('Michael Lee', 'Compatibility', 'Does not work on Internet Explorer', '2024-03-05', 2),
   ('Tyrone Johnson', 'UI', 'Font size is too small', '2024-03-06', 3),
   ('David Martinez', 'Performance', 'Search feature is slow', '2024-03-07', 4),
   ('Fatima Abadi', 'Functionality', 'Logout button not working', '2024-03-08', 3),
   ('William Taylor', 'Security', 'Sensitive data exposed in logs', '2024-03-09', 7),
   ('Nikolai Petrov', 'Compatibility', 'Not compatible with Safari', '2024-03-10', 2);
   

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3. Edit the Streamlit app code with the following example:

   import streamlit as st
   
   session = st.connection('snowflake').session()
   
   # Change the query to point to your table
   def get_data(_session):
       query = """
       select * from <your_database>.<your_schema>.BUG_REPORT_DATA
       order by date desc
       limit 100
       """
       data = _session.sql(query).collect()
       return data
   
   # Change the query to point to your table
   def add_row_to_db(session, row):
       sql = f"""INSERT INTO <your_database>.<your_schema>.BUG_REPORT_DATA VALUES
       ('{row['author']}',
       '{row['bug_type']}',
       '{row['comment']}',
       '{row['date']}',
       '{row['bug_severity']}')"""
   
       session.sql(sql).collect()
   
   st.set_page_config(page_title="Bug report", layout="centered")
   
   st.title("Bug report demo!")
   
   st.sidebar.write(
       f"This app demos how to read and write data from a Snowflake Table"
   )
   
   form = st.form(key="annotation", clear_on_submit=True)
   
   with form:
       cols = st.columns((1, 1))
       author = cols[0].text_input("Report author:")
       bug_type = cols[1].selectbox(
           "Bug type:", ["Front-end", "Back-end", "Data related", "404"], index=2
       )
       comment = st.text_area("Comment:")
       cols = st.columns(2)
       date = cols[0].date_input("Bug date occurrence:")
       bug_severity = cols[1].slider("Bug priority :", 1, 5, 2)
       submitted = st.form_submit_button(label="Submit")
   
   if submitted:
       try:
           add_row_to_db(
               session,
               {'author':author,
               'bug_type': bug_type,
               'comment':comment,
               'date':str(date),
               'bug_severity':bug_severity
           })
           st.success("Thanks! Your bug was recorded in the database.")
           st.balloons()
       except Exception as e:
           st.error(f"An error occured: {e}")
   
   expander = st.expander("See 100 most recent records")
   with expander:
       st.dataframe(get_data(session))
   

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4. Select Run to run the Streamlit app.