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+## Lecture 1 (13:00) - More SQL
+
+### Attribute Alias
+
+```sql
+SELECT driverID AS DriverNumber
+FROM Drivers;
+```
+
+### Distinct
+
+```sql
+SELECT address FROM Drivers WHERE DriverID IN (D020, D030)
+```
+
+#### Output:
+
+| address |
+|---------|
+| Dundee |
+| Dundee |
+
+```sql
+SELECT DISTINCT address FROM Drivers WHERE DriverID IN (D020, D030)
+```
+
+#### Output:
+
+| address |
+|---------|
+| Dundee |
+
+### Aggregate Functions
+
+- **sum()** - Adds all inputs
+- **avg()** - Mean average of all inputs
+- **count()** - Count total records of input
+- **max()** - Get maximum value of inputs
+- **min()** - Get minimum value of inputs
+
+### Group By
+
+```sql 
+SELECT address, COUNT(niNo)
+FROM Employees
+GROUP BY address;
+```
+
+#### Output:
+
+| Address | count(niNo) |
+|---------|--------------|
+| Aberdeen | 2 |
+| Dundee | 2 |
+| Stirling | 1 |
+
+### Having Clause
+
+- Used with group by to filter groups / rows
+
+```sql
+SELECT <attributes>, <column functions>
+FROM <tables>
+WHERE <conditions> //Optional
+GROUP BY <attributes>
+HAVING <conditions>;
+```
+
+![](Pasted%20image%2020231003133326.png)
+
+```sql
+SELECT address, AVG(salary)
+FROM Employees
+GROUP BY address
+HAVING AVG(salary) > 21000;
+```
+
+#### Output:
+
+| address | avg(salary) |
+|---|----|
+| Dundee | 22500 |
+
+### Having Vs. Where
+
+- **WHERE** removes rows *before* grouping
+- **HAVING** filters groups
+- Aggregate functions cannot be used with the **WHERE** clause.
+
+### Update Queries
+
+- Allows you to change the values of attributes of existing rows ( tuples ) of a table
+
+```sql
+UPDATE <table>
+SET <attribute assignments>
+WHERE <conditions>; //optional
+```
+
+```sql
+UPDATE Drivers
+SET points = 6
+WHERE driverID = "D040";
+```
+
+#### Output:
+
+![](Pasted%20image%2020231003134123.png)
+
+```sql
+UPDATE Drivers
+SET address = "Salford"
+WHERE driverID = "D020";
+```
+
+![](Pasted%20image%2020231003134231.png)
+
+### Delete Queries
+
+- Deletes whole rows ( tuples ), not individual values
+
+```sql
+DELETE FROM <table name>
+WHERE <conditions>; //optional
+```
+
+```sql
+DELETE FROM Drivers
+WHERE points > 10;
+```
+
+#### Output
+
+![](Pasted%20image%2020231003134528.png)
+
+### Insert Queries
+
+- Adds data to existing table without deleting it or any records
+
+```sql
+INSERT INTO <table name> <attribute list> //optional
+SELECT <statement> | VALUES <value list>;
+```
+
+```sql
+INSERT INTO Drivers
+VALUES ("D060", "Betty", "Inverness", 6);
+```
+
+#### Output
+
+![](Pasted%20image%2020231003134918.png)
+
+```sql
+INSERT INTO Drivers (driverID, name)
+VALUES ("D070", "Jeannie")
+```
+
+#### Output
+
+![](Pasted%20image%2020231003135010.png)
+
+## Lecture 2 (15:00) - More SQL
+
+### Data Types
+
+```sql
+CHARACTER(L)
+```
+
+- Fixed length character string containing L letters. Fewer characters are used as padding.
+
+```sql
+CHARACTER VARYING(L)
+```
+
+- Variable length character string that holds up to L characters. No padding.
+
+```sql
+INTEGER(L)
+```
+
+- Signed whole number.
+
+```sql
+NUMERIC(P,S)
+```
+
+- P = Precision. Total number of digits
+- S = Scale. Number of digits to correct decimal place.
+- Ex. NUMERIC(5,2) is `-999.99` to `999.99`
+
+```sql
+DATE YYYY-MM-DD
+```
+
+- YYYY = `1` to `9999`
+- MM = `1` to `12`
+- DD = `1` to `31
+
+```sql
+TIME HH:MM:SS
+```
+
+- HH = Hours
+- MM = Minutes
+- SS = Seconds
+
+```sql
+TIMESTAMP YYYY-MM-DD HH:MM:SS
+```
+
+- Combination of DATE and TIME
+
+```sql
+INTERVAL
+```
+
+- Refers to period of time. May have value such as `90 days`. Also known as a span
+
+```sql
+BINARY LARGE OBJECT(L)
+```
+
+- Large, variable length binary string that can hold up to L bytes. Also known as `BLOB`
+
+```sql
+BOOLEAN
+```
+
+- Value of TRUE or FALSE
+
+```sql
+NULL
+```
+
+- Value of unknown, valid for any data type.
+
+#### Exercise
+
+1. CHAR
+2. DATE
+3. BOOLEAN
+4. INTEGER
+5. NUMERIC
+6. CHAR(10) = Bryant____
+7. VARCHAR(10) = Bryant
+8. INTEGER can have the value NULL
+
+### Exercise on Data Types and Keys
+
+1. Book
+	1. ISBN - VARCHAR
+	2. Title - VARCHAR
+	3. Author - VARCHAR
+2. Members
+	1. MemID - CHAR
+	2. Name - VARCHAR
+	3. Age - INTEGER
+	4. Address - VARCHAR
+	5. Phone - VARCHAR
+3. Loan
+	1. LoanID - CHAR
+	2. ISBN ( Foreign Key )
+	3. MemID ( Foreign Key )
+	4. LoanDate - DATE
+	5. ReturnDate - DATE
+
+### Exercise on Adding, Deleting and Modifying Data
+
+1. Append tuple to pirates table
+
+```SQL
+INSERT INTO Pirates
+VALUES ("p5", "Pegleg", 1, 2, "Spain");
+```
+
+```SQL
+INSERT INTO Boats (boat-code, boat-name, origin)
+VALUES ("b9", "Swift", "British");
+```
+
+```SQL
+INSERT INTO Booty
+VALUES ("bt13", "Flour", 8);
+```
+
+1. Change the name of Booty "bt8" from "nothing" to "infected animals"
+
+```sql
+UPDATE Booty
+SET booty-name = "Infected Animals"
+WHERE booty-code = "bt8";
+```
+
+1. Remove b7 from the boats table
+
+```sql 
+DELETE FROM Boats
+WHERE boat-code = "b7";
+```
+
+### Exercise on Aggregating Results
+
+#### Exercise
+
+1. Calculate total value of all booty in booty table
+
+```sql 
+SELECT SUM(value)
+FROM booty;
+```
+
+1. List each type of boat, with the number of boats with that type
+
+```sql
+SELECT boat-type, COUNT (boat-code)
+FROM boats;
+```
+
+- Remember comma between select and aggregate functions
+
+## Workshop 1 (10:00)
+
+![](Pasted%20image%2020231006102147.png)
+
+1. List the unit price of the cheapest product.
+![](Pasted%20image%2020231006102426.png)
+2. What is the total value of all the products?
+![](Pasted%20image%2020231006102826.png)
+3. How many products have been discontinued?
+![](Pasted%20image%2020231006102943.png)
+4. What is the average unit price of the products which have been discontinued?
+![](Pasted%20image%2020231006103041.png)
+5. Display the name of every supplier and the total number of products supplied by
+that company.
+![](Pasted%20image%2020231006104220.png)
+6. Display total number of orders for each employee.
+![](Pasted%20image%2020231006104753.png)