finish Assignment 1

02_activities/assignments/DC_Cohort/Assignment1.md

@@ -209,5 +209,5 @@ Consider, for example, concepts of fariness, inequality, social structures, marg
 
 
 ```
-Your thoughts...
+Databases might seem like just a technical tool for storing information, but after reading this article, I started to realize they actually reflect certain values and assumptions. For example, the system described in the article assumes that everyone fits into a traditional family structure, which is not true for many people. Because of this, some individuals were excluded or faced difficulties when the database could not recognize their situation. This made me think that databases can create unfairness, even if that is not the intention. In my everyday life, I also see similar situations, like when filling out forms that only allow limited options for gender or family background. These systems simplify people’s identities, but in doing so, they may ignore important differences and experiences. As someone new to this topic, I am beginning to understand that technology is not neutral, and the way databases are designed can shape how people are treated in society.
 ```

02_activities/assignments/DC_Cohort/assignment1.sql

@@ -6,28 +6,28 @@
 --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. */
-
-
+SELECT *
+FROM customer_purchases
+WHERE product_id IN (4,9)
+LIMIT 25;
 
 /*2. Write a query that returns all customer purchases and a new calculated column 'price' (quantity * cost_to_customer_per_qty), 
 filtered by customer IDs between 8 and 10 (inclusive) using either:
@@ -36,10 +36,11 @@ filtered by customer IDs between 8 and 10 (inclusive) using either:
 Limit to 25 rows of output.
 */
 --QUERY 3
-
-
-
-
+SELECT *
+,quantity * cost_to_customer_per_qty AS price
+FROM customer_purchases
+WHERE customer_id BETWEEN 8 AND 10
+LIMIT 25;
 --END QUERY
 
 
@@ -49,47 +50,60 @@ 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 4
-
-
-
-
+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 5
-
-
-
-
+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
 
-
 --JOIN
 /* 1. Write a query that INNER JOINs the vendor table to the vendor_booth_assignments table on the 
 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 6
-
-
-
-
+SELECT *
+FROM vendor v
+INNER JOIN vendor_booth_assignments vba
+    ON v.vendor_id = vba.vendor_id
+ORDER BY vba.market_date, v.vendor_name
+LIMIT 24;
 --END QUERY
 
 
-
 /* SECTION 3 */
 
 -- AGGREGATE
 /* 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 7
-
-
-
-
+SELECT 
+    vendor_id,
+    COUNT(*) AS booth_count
+FROM vendor_booth_assignments
+GROUP BY vendor_id;
 --END QUERY
 
 
@@ -99,13 +113,24 @@ 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 8
-
-
-
-
+SELECT
+    c.customer_id,
+    c.customer_first_name,
+    c.customer_last_name,
+    SUM(cp.quantity * cp.cost_to_customer_per_qty) AS total_spent
+FROM customer c
+INNER JOIN customer_purchases cp
+    ON c.customer_id = cp.customer_id
+GROUP BY
+    c.customer_id,
+    c.customer_first_name,
+    c.customer_last_name
+HAVING SUM(cp.quantity * cp.cost_to_customer_per_qty) > 2000
+ORDER BY c.customer_last_name, c.customer_first_name;
 --END QUERY
 
 
+
 --Temp Table
 /* 1. Insert the original vendor table into a temp.new_vendor and then add a 10th vendor: 
 Thomass Superfood Store, a Fresh Focused store, owned by Thomas Rosenthal
@@ -118,10 +143,24 @@ When inserting the new vendor, you need to appropriately align the columns to be
 VALUES(col1,col2,col3,col4,col5) 
 */
 --QUERY 9
-
-
-
-
+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
 
 
@@ -132,10 +171,12 @@ 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 10
-
-
-
-
+SELECT
+    customer_id,
+    STRFTIME('%m', market_date) AS month,
+    STRFTIME('%Y', market_date) AS year
+FROM customer_purchases
+LIMIT 25;
 --END QUERY
 
 
@@ -146,8 +187,13 @@ 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 11
+SELECT
+    customer_id,
+    SUM(quantity * cost_to_customer_per_qty) AS total_spent
+FROM customer_purchases
+WHERE STRFTIME('%m', market_date) = '04'
+  AND STRFTIME('%Y', market_date) = '2022'
+GROUP BY customer_id;
+--END QUERY
 
 
-
-
---END QUERY

04_this_cohort/Mar26_Live code.sql

@@ -0,0 +1,46 @@
+/* MODULE 2 */
+/* LEFT  JOIN */
+
+
+/* 1. There are products that have been bought
+... but are there products that have not been bought? 
+Use a LEFT JOIN to find out*/
+SELECT DISTINCT
+p.product_id
+,cp.product_id as [cp.product_id]
+,product_name
+
+FROM product as p
+LEFT JOIN customer_purchases as cp
+	ON p.product_id =  cp.product_id
+
+/* 2. Directions of LEFT JOINs matter ...*/
+
+FROM customer_purchases as cp
+LEFT JOIN product as p
+	ON p.product_id = cp.product_id;
+
+
+/* 3. As do which values you filter on ... */
+SELECT DISTINCT
+p.product_id
+,cp.product_id
+
+
+
+/* 4. Without using a RIGHT JOIN, make this query return the RIGHT JOIN result set
+...**Hint, flip the order of the joins** ...
+
+SELECT *
+
+FROM product_category AS pc
+LEFT JOIN product AS p
+	ON pc.product_category_id = p.product_category_id
+	ORDER by pc.product_category_id
+
+...Note how the row count changed from 24 to 23
+*/	
+
+
+
+--------------------------------------------------------------------------------------------------------------------------------------------