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+## Lecture 1 (13:00) - Conceptual Modelling
+
+### Role of Conceptual Modelling
+
+- Real world problem -> Conceptual Model Data -> Logical Data Model -> Physical Model (DBMS)
+	- Identify important concepts and data needs, creating a conceptual model.
+- Many different ways to get to the same solution.
+- Iterative process - if one method does not work, it can be revised.
+
+### Conceptual Data Model
+
+- Abstract view of situation.
+	- Identifies important elements and relationships between them. (ex. Library: Books, Members, ~~Carpets~~)
+	- Human interact-able, not computer terms.
+	- Implementation Independent.
+	- Useful for client brief.
+
+### Reasons for Using ER Modelling
+
+- Simpler and easier to understand than database tables
+	- Helps discussions with clients and colleagues
+- Allows for segmentation of work.
+	- Modelling real world solution
+	- Designing DB tables
+- Most large organisations will require it
+
+### Obtaining an ER Model
+
+- Given a spec, you need to identify:
+	- entities - 'things' with physical or conceptual existence
+	- relationships
+	- attributes
+	- constraints or assumptions
+
+#### Example
+
+Departments control many projects and each department has many employees. Each employee works on only one project at a time. A project’s start date must be before the project’s target completion date. Each employee has an NI number, name and address
+
+Entities:
+
+- departments
+- projects
+- employees
+Relationships:
+- **control** between departments and projects
+- **has between** departments and employees
+- **works on** between employees and projects
+Attributes:
+- startdate
+- completiondate
+- ninumber
+- name
+- address
+Constraints:
+- Start date must be before the target completion date
+
+### ER Diagram
+
+![](Pasted%20image%2020231017132317.png)
+
+- Many different notations
+- One is "crows foot":
+![](Pasted%20image%2020231017132357.png)
+![](Pasted%20image%2020231017133438.png)
+![](Pasted%20image%2020231017133451.png)
+
+## Lecture 3 (16:00)
+
+1. Generate a list of the ages of ATMs whose security level is normal. The list should be in descending order.
+
+```sql
+SELECT age
+FROM atm
+WHERE security-level = "normal"
+ORDER BY age DESC;
+```
+
+2. List the name of each bank which has a branch whose address starts with the word Eccles. The list should not include any duplicates.
+
+```sql
+SELECT DISTINCT name
+FROM bank, branch
+WHERE Bank.bankID = Branch.bankID 
+AND address LIKE "Eccles*";
+```
+
+3. Calculate the average age of the ATMs with low or normal levels of security. Name the results column “Average age”.
+
+```sql
+SELECT AVG(age) AS "Average Age"
+FROM atm
+WHERE security-level = "low" OR security-level = "normal";
+```
+
+4. Remove the tuple from the relation ATM whose identifier is atm04.
+
+```sql
+DELETE FROM atm
+WHERE atmID = "atm04";
+```
+
+5. Add a row for an ATM, whose atmID is atm05, whose security level is high and which is located at branch T1.
+
+```sql
+INSERT INTO atm 
+VALUES ("atm05", "high", "0", "T1");
+```
+
+6. Add an attribute called telephone number to the relation Branch.
+
+```sql
+ALTER TABLE branch
+ADD telephone CHAR(15)
+```
+
+7. Set the address of every branch to the value Salford.
+
+```sql
+UPDATE branch
+SET address = "Salford";
+```
+
+1) Bank LEFT OUTER JOIN Branch
+```sql
+SELECT *
+FROM bank
+INNER JOIN 
+```