JTD SQL Assignment 1

02_activities/assignments/DC_Cohort/Assignment1.md

@@ -209,5 +209,13 @@ Consider, for example, concepts of fariness, inequality, social structures, marg
 
 
 ```
-Your thoughts...
+Databases are often considered objective sources of information, but their design can influence how individuals are categorized and represented. Qadri's article illustrates this through Pakistan's national identification database, where assumptions about family structures and marriage can prevent individuals from accessing essential services. This shows how decisions about data collection and organization can reinforce existing inequalities.
+
+In my work in health services research, I use administrative healthcare databases to study healthcare utilization, costs and outcomes. These databases were primarily developed for administrative purposes rather than research. As a result, they capture hospitalizations, physician visits and healthcare costs, but often lack information about patients' experiences and unmet healthcare needs.
+
+For example, patients with fewer healthcare encounters may appear to have lower healthcare needs. However, lower utilization may actually result from financial, geographical or social barriers to accessing care. If we interpret utilization as a measure of need, we risk underestimating the needs of disadvantaged populations.
+
+Similarly, demographic characteristics such as sex, gender and socioeconomic status are often recorded using predefined categories that may not adequately capture differences within populations. This can affect how we identify and measure health inequities.
+
+I think these limitations are particularly important because research findings can inform healthcare policy and resource allocation. Qadri's article highlights that databases are not neutral. As researchers, we need to consider what information is captured, what is missing and how these decisions may influence our findings and potentially reinforce existing inequities.
 ```

02_activities/assignments/DC_Cohort/assignment1.sql

@@ -6,31 +6,30 @@
 --SELECT
 /* 1. Write a query that returns everything in the customer table. */
 --QUERY 1
-
-
-
-
+SELECT *
+FROM customer;
 --END QUERY
 
 
 /* 2. Write a query that displays all of the columns and 10 rows from the customer table, 
 sorted by customer_last_name, then customer_first_ name. */
 --QUERY 2
-
-
-
-
+SELECT *
+FROM customer
+ORDER BY customer_last_name, 
+		 customer_first_name
+LIMIT 10;
 --END QUERY
 
 
 --WHERE
 /* 1. Write a query that returns all customer purchases of product IDs 4 and 9. 
 Limit to 25 rows of output. */
 --QUERY 3
-
-
-
-
+SELECT *
+FROM customer_purchases
+WHERE product_id IN (4, 9)
+LIMIT 25;
 --END QUERY
 
 
@@ -42,10 +41,10 @@ filtered by customer IDs between 8 and 10 (inclusive) using either:
 Limit to 25 rows of output.
 */
 --QUERY 4
-
-
-
-
+SELECT *, quantity * cost_per_quantity AS price
+FROM customer_purchases
+WHERE customer_id BETWEEN 8 AND 10
+LIMIT 25;
 --END QUERY
 
 
@@ -55,21 +54,31 @@ Using the product table, write a query that outputs the product_id and product_n
 columns and add a column called prod_qty_type_condensed that displays the word “unit” 
 if the product_qty_type is “unit,” and otherwise displays the word “bulk.” */
 --QUERY 5
-
-
-
-
+SELECT product_id, 
+	   product_name,
+	CASE 
+		WHEN product_qty_type = 'unit' THEN 'unit'
+		ELSE 'bulk'
+	END AS prod_qty_type_condensed
+FROM product;
 --END QUERY
 
 
 /* 2. We want to flag all of the different types of pepper products that are sold at the market. 
 add a column to the previous query called pepper_flag that outputs a 1 if the product_name 
 contains the word “pepper” (regardless of capitalization), and otherwise outputs 0. */
 --QUERY 6
-
-
-
-
+SELECT product_id, 
+	   product_name,
+	CASE 
+		WHEN product_qty_type = 'unit' THEN 'unit'
+		ELSE 'bulk'
+	END AS prod_qty_type_condensed,
+	CASE 
+		WHEN LOWER(product_name) LIKE '%pepper%' THEN 1
+		ELSE 0
+	END AS pepper_flag
+FROM product;
 --END QUERY
 
 
@@ -78,10 +87,13 @@ contains the word “pepper” (regardless of capitalization), and otherwise out
 vendor_id field they both have in common, and sorts the result by market_date, then vendor_name.
 Limit to 24 rows of output. */
 --QUERY 7
-
-
-
-
+SELECT *
+FROM vendor
+INNER JOIN vendor_booth_assignments
+ON vendor.vendor_id = vendor_booth_assignments.vendor_id
+ORDER BY market_date, 
+		 vendor_name
+LIMIT 24;
 --END QUERY
 
 
@@ -92,10 +104,10 @@ Limit to 24 rows of output. */
 /* 1. Write a query that determines how many times each vendor has rented a booth 
 at the farmer’s market by counting the vendor booth assignments per vendor_id. */
 --QUERY 8
-
-
-
-
+SELECT vendor_id, 
+	   COUNT(*) AS booth_rentals
+FROM vendor_booth_assignments
+GROUP BY vendor_id;
 --END QUERY
 
 
@@ -105,10 +117,19 @@ of customers for them to give stickers to, sorted by last name, then first name.
 
 HINT: This query requires you to join two tables, use an aggregate function, and use the HAVING keyword. */
 --QUERY 9
-
-
-
-
+SELECT customer.customer_id, 
+	   customer_first_name, 
+	   customer_last_name, 
+	   SUM(quantity * cost_per_quantity) AS total_spent
+FROM customer
+INNER JOIN customer_purchases
+ON customer.customer_id = customer_purchases.customer_id
+GROUP BY customer.customer_id, 
+		 customer_first_name, 
+		 customer_last_name
+HAVING SUM(quantity * cost_per_quantity) > 2000
+ORDER BY customer_last_name, 
+		 customer_first_name;
 --END QUERY
 
 
@@ -124,10 +145,19 @@ When inserting the new vendor, you need to appropriately align the columns to be
 VALUES(col1,col2,col3,col4,col5) 
 */
 --QUERY 10
-
-
-
-
+CREATE TEMP TABLE new_vendor AS
+SELECT *
+FROM vendor;
+INSERT INTO new_vendor (vendor_id, 
+						vendor_name, 
+						vendor_type, 
+						vendor_owner_first_name, 
+						vendor_owner_last_name)
+VALUES (10, 
+		'Thomass Superfood Store', 
+		'Fresh Focused', 
+		'Thomas', 
+		'Rosenthal');
 --END QUERY
 
 
@@ -138,10 +168,11 @@ HINT: you might need to search for strfrtime modifers sqlite on the web to know
 and year are! 
 Limit to 25 rows of output. */
 --QUERY 11
-
-
-
-
+SELECT customer_id,
+       STRFTIME('%m', market_date) AS month,
+       STRFTIME('%Y', market_date) AS year
+FROM customer_purchases
+LIMIT 25;
 --END QUERY
 
 
@@ -152,8 +183,10 @@ HINTS: you will need to AGGREGATE, GROUP BY, and filter...
 but remember, STRFTIME returns a STRING for your WHERE statement...
 AND be sure you remove the LIMIT from the previous query before aggregating!! */
 --QUERY 12
-
-
-
-
+SELECT customer_id,
+       SUM(quantity * cost_per_quantity) AS total_spent
+FROM customer_purchases
+WHERE STRFTIME('%m', market_date) = '04'
+AND STRFTIME('%Y', market_date) = '2022'
+GROUP BY customer_id;
 --END QUERY