Filtering on multiple conditions

So far, you've selectively imported records that met a single condition, but it's also common to filter datasets on multiple criteria. In this exercise, you'll do just that.

The weather table contains daily high and low temperatures and precipitation amounts for New York City. Let's focus on inclement weather, where there was either an inch or more of snow or the high was at or below freezing (32° Fahrenheit). To do this, you'll need to build a query that uses the OR operator to look at values in both columns.

pandas is loaded as pd, and a database engine, engine, has been created.

This exercise is part of the course

Streamlined Data Ingestion with pandas

View Course

Exercise instructions

Create a query that selects records in weather where tmax is less than or equal to 32 degrees OR snow is greater than or equal to 1 inch.
Use read_sql() to query the database and assign the result to the variable wintry_days.
View summary statistics with the describe() method to make sure all records in the dataframe meet the given criteria.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Create query for records with max temps <= 32 or snow >= 1
query = """
SELECT *
  FROM weather
  ____ ____
  ____ ____;
"""

# Query database and assign result to wintry_days
wintry_days = pd.read_sql(____)

# View summary stats about the temperatures
print(____)

Edit and Run Code