chore: use polars instead of pandas in examples (#3289)

* Migrate the SQL examples to use Polars.
* Can merge when polars in pyodide is supported

examples/sql/connect_to_motherduck.py

@@ -3,8 +3,9 @@
 # dependencies = [
 #     "altair==5.4.1",
 #     "duckdb==1.1.0",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "marimo",
-#     "pandas==2.2.3",
 # ]
 # ///
 

examples/sql/connect_to_postgres.py

@@ -3,7 +3,8 @@
 # dependencies = [
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "requests==2.32.3",
 # ]
 # ///

examples/sql/connect_to_sqlite.py

@@ -3,19 +3,20 @@
 # dependencies = [
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "requests==2.32.3",
 # ]
 # ///
 
 import marimo
 
-__generated_with = "0.9.1"
+__generated_with = "0.10.7"
 app = marimo.App(width="medium")
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(
         r"""
         # Connect to SQLite
@@ -31,7 +32,7 @@ def __(mo):
 
 
 @app.cell(hide_code=True)
-def __():
+def _():
     import marimo as mo
 
 
@@ -53,7 +54,7 @@ def download_sample_data():
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.accordion(
         {
             "Tip: Creating SQL Cells": mo.md(
@@ -73,7 +74,7 @@ def __(mo):
 
 
 @app.cell
-def __(INFORMATION_SCHEMA, mo):
+def _(INFORMATION_SCHEMA, TABLES, mo):
     _df = mo.sql(
         f"""
         -- Boilerplate: detach the database so this cell works when you re-run it
@@ -90,13 +91,13 @@ def __(INFORMATION_SCHEMA, mo):
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(r"""Once the database is attached, you can query it with SQL. For example, the next cell computes the average track length of each composer in the chinook database.""")
     return
 
 
 @app.cell
-def __(chinook, mo, track):
+def _(chinook, mo, track):
     _df = mo.sql(
         f"""
         SELECT composer, MEAN(Milliseconds) as avg_track_ms from chinook.track GROUP BY composer ORDER BY avg_track_ms DESC;
@@ -106,7 +107,7 @@ def __(chinook, mo, track):
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(
         f"""
         You can explore the schemas of all your tables at a glance in the **data sources panel**: click

examples/sql/misc/database_explorer.py

@@ -3,7 +3,8 @@
 # dependencies = [
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 # ]
 # ///
 

examples/sql/misc/electric_vehicles.py

@@ -2,7 +2,10 @@
 # requires-python = ">=3.9"
 # dependencies = [
 #     "altair==5.4.1",
+#     "duckdb==1.1.3",
 #     "marimo",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 # ]
 # ///
 

examples/sql/misc/sql_cars.py

@@ -4,7 +4,8 @@
 #     "altair==5.4.1",
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "vega-datasets==0.9.0",
 # ]
 # ///
@@ -233,11 +234,10 @@ def __(cars, mo, selected_cars):
 @app.cell
 def __():
     import marimo as mo
-    import pandas as pd
     import duckdb
     import altair as alt
     from vega_datasets import data
-    return alt, data, duckdb, mo, pd
+    return alt, data, duckdb, mo
 
 
 if __name__ == "__main__":

examples/sql/parametrizing_sql_queries.py

@@ -3,7 +3,8 @@
 # dependencies = [
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "vega-datasets==0.9.0",
 # ]
 # ///

examples/sql/querying_dataframes.py

@@ -3,7 +3,8 @@
 # dependencies = [
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "vega-datasets==0.9.0",
 # ]
 # ///

examples/sql/read_csv.py

@@ -3,19 +3,20 @@
 # dependencies = [
 #     "duckdb==1.1.1",
 #     "marimo",
-#     "pandas==2.2.3",
+#     "polars==1.18.0",
+#     "pyarrow==18.1.0",
 #     "vega-datasets==0.9.0",
 # ]
 # ///
 
 import marimo
 
-__generated_with = "0.9.1"
+__generated_with = "0.10.7"
 app = marimo.App(width="medium")
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(
         """
         # Read CSV
@@ -27,22 +28,22 @@ def __(mo):
 
 
 @app.cell(hide_code=True)
-def __():
+def _():
     import marimo as mo
-    import pandas as pd
+    import polars as pl
 
-    pd.DataFrame({"A": [1, 2, 3], "B": ["a", "b", "c"]}).to_csv("data.csv")
-    return mo, pd
+    pl.DataFrame({"A": [1, 2, 3], "B": ["a", "b", "c"]}).write_csv("data.csv")
+    return mo, pl
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md("""Reading from a local CSV is as easy as `SELECT * from "data.csv"`, where `data.csv` is the path to your local file (or a URL to a CSV file).""")
     return
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.accordion(
         {
             "Tip: Creating SQL Cells": mo.md(
@@ -62,19 +63,20 @@ def __(mo):
 
 
 @app.cell
-def __(data, mo):
+def _(mo):
     result = mo.sql(
         f"""
         -- Tip: you can also specify the data files using a glob, such as '/path/to/*.csv'
         -- or '/path/**/to/*.csv'
         SELECT * FROM "data.csv"
-        """, output=False
+        """,
+        output=False,
     )
     return (result,)
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.accordion(
         {
             "Tip: Query output": mo.md(
@@ -92,13 +94,13 @@ def __(mo):
 
 
 @app.cell
-def __(result):
+def _(result):
     result
     return
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(
         r"""
         ## Create an in-memory table from a CSV file
@@ -110,7 +112,7 @@ def __(mo):
 
 
 @app.cell
-def __(data, mo):
+def _(mo):
     _df = mo.sql(
         f"""
         CREATE TABLE myTable AS SELECT * FROM "data.csv"
@@ -120,7 +122,7 @@ def __(data, mo):
 
 
 @app.cell
-def __(mo, myTable):
+def _(mo, myTable):
     _df = mo.sql(
         f"""
         SELECT * FROM myTable
@@ -130,13 +132,13 @@ def __(mo, myTable):
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(r"""## Advanced usage""")
     return
 
 
 @app.cell(hide_code=True)
-def __(mo):
+def _(mo):
     mo.md(r"""To customize how your CSV is read, including specifying the delimiter type, use [duckdb's `read_csv` function](https://duckdb.org/docs/data/csv/overview.html).""")
     return