These are the projects that I worked on in my PostgreSQL class - INST123 - Database for All at University of Maryland - College Park.

Here is a brief summary of the projects:

1) Project 1/Assignment 1: Basic SELECT Queries

In this project I wrote two queries that replicate the result set in two tables, matching all data, including row order.

2) Project 2/Assignment 2: Import and Export

In this project I wrote a query that replicates the result set in a table, matching all data, including row order. In question 2, I exported data from the us_counties_2010 table for California, Texas, and Alaska to create a CSV file named large_states.csv. Then, I created the large_states table in pgAdmin and imported the data from large_states.csv file I created into the large_states table.

3) Project 3/Assignment 3: Multi-table and Aggregate Queries

In this project there are two library tables (FY2009 and FY2014). The question 1 is about using appropriate JOINS and selecting the records with NULL values, identify which library systems existed in FY2009 that did not exist in FY2014. Then, in question 2, I calculated the percent change in the number of ebooks in each state/territory from FY2009 to FY2014.

4) Project 4/Assignment 4: Modifying Data - Working with Dates and Times

In question 1, I turned data in the activities column of the meat_poultry_egg_inspect table into useful information to answer three questions that are "How many companies process poultry?", "How many companies process meat?" and "How many companies have export certification?". In question 2, based on the New York City taxi data in the nyc_yellow_taxi_trips_2016_06_01 table, I calculated the length of each ride using the pickup and drop-off timestamps and filtered the results to display trips that were at least 1 hour long, but shorter than 2.5 hours.

5) Project 5: Team Project Final Deliverable and Report

With billions of people using social media every day, social media has quickly become a major part of our daily lives in the past few years. Whether it is people posting about their lives, people posting videos about certain events, or even businesses advertising their products, social media is what allows information to flow to people around the world. This is why my team chose our topic to be social media usage in 2022.
Our social media database was based on statistics as of 2022. To analyze the data, we created a database that tracks critical information to better understand how social media usage was spread across the world. It included data regarding the social media users popularity ranking, the age of the user base, their gender, their social media using behaviors, and the social media usage within different countries. We split these into multiple tables that cover different categories within our database. The tables consist of the different social media platforms that exist such as Facebook, YouTube, Instagram, etc., the different regions such as South America, North America, etc. and the different countries such as India, China, etc.