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Functions for Manipulating Data in PostgreSQL

Here you can access the tables used in the course. To access the table, you will need to specify the dvdrentals schema in your queries (e.g., dvdrentals.film for the film table and dvdrentals.country for the country table).

Take Notes

Add notes about the concepts you've learned and SQL cells with queries you want to keep.

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DataFrameas
movie_info
variable
-- Add your own queries here
SELECT 
  UPPER(c.name) || ': ' || f.title AS film_category, 
  -- Truncate the description without cutting off a word
  LEFT(description, 50 - 
    -- Subtract the position of the first whitespace character
    POSITION(' ' IN REVERSE(LEFT(description, 50)))) AS no_cutoff
FROM 
  dvdrentals.film AS f 
  INNER JOIN dvdrentals.film_category AS fc 
  	ON f.film_id = fc.film_id 
  INNER JOIN dvdrentals.category AS c 
  	ON fc.category_id = c.category_id;

Explore Datasets

Use the different tables to explore the data and practice your skills!

  • Select the title, release_year, and rating of films in the film table.
    • Add a description_shortened column which contains the first 50 characters of the description column, ending with "...".
    • Filter the film table for rows where the special_features column contains "Commentaries".
  • Select the customer_id, amount, and payment_date from the payment table.
    • Extract date information from the payment_date column, creating new columns for the day, month, quarter, and year of transaction.
    • Use the rental table to include a column containing the number of days rented (i.e., time between the rental_date and the return_date).
  • Update the title column so that titles with multiple words are reduced to the first word and the first letter of the second word followed by a period.
    • For example:
      • "BEACH HEARTBREAKERS" becomes "BEACH H."
      • "BEAST HUNCHBACK" becomes "BEAST H."
    • Reformat your shortened title to title case (e.g., "BEACH H." becomes "Beach H.").