1. Relationships

2. “ Situation that exists between two relational database tables”  It stop the need for repeating data  Allows the database to be smaller in size  Makes it easier to update, add and delete information  It also makes searching the database easier

3. Data Redundancy idnameDobphoneclassTutorRoom 356Jess3 Mar 199512345 6789045BMr Noggin56 412Hamad12 Nov 199467890 2345927XMr Noggin56 459Sita9 Jan 199412345 7654345BMs Take18 502James10 March 199309876 654326BMr Noggin56 This is a flat file database, boo hiss!!! The problem is that we have redundancy

4. How to solve the issue  Simply take the data out  Make another table idnameDobphoneclassTeacher 356Jess3 Mar 199512345 6789045B1 412Hamad12 Nov 199467890 2345927X1 459Sita9 Jan 199412345 7654345B2 502James10 March09876 654326B1 idtutorroom 1 Mr Noggin56 2 Ms Take18 Students Teachers

5. Different types of relationship  One to One  A persons credit check  One to Many  A teacher and students  Many to Many  Online orders Table 1 Table 2 Table 1 Table 2 Table 1 Table 2 Important Fact This can never be made, as the database wont allow it

6. The Task  You need to design a second table in your ERD for actors  Then you need to build the table  Add some actors into your table and link them with films. Extension Challenge Try and find the problem with using a 1 to many relationship Extension Challenge Try and find the problem with using a 1 to many relationship