2Lesson №56 Primary key in Database Presentation

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Let’s recap the the last topic
The main Database Concepts

Assessment
prior knowledge

Lesson 56
10.4А Information systems
Theme:
Primary key in database
Lesson objectives:
Define the primary key in database

Assessment criteria
Understanding:
-list types of keys in Database
Synthesis :
-make the definition of primary key
-make the definition of foreign key
Analyses:
-distinguish the differences between types of keys in Database
-define primary key in Database

Watching the video
Questions for discussion:
1. What types of keys are in the database?
2. Why do I need a primary key?
3. What is a foreign key?
4. How many tables are considered on the example?
5. How to distinguish a primary key from a foreign key?

Discussion
Questions for discussion:
1. What types of keys are in the database?
2. Why do I need a primary key?
3. What is a foreign key?
4. How many tables are considered on the example?
5. How to distinguish a primary key from a foreign key?

The primary key is
cannot have the same primary key values.
Primary key usually
one example of unique indices and
None of the two table entries
used to uniquely identify table entries.
abbreviated as PK (primary key)

The primary key is one example of unique indexes and is used to uniquely identify table entries. None of the two table entries can have the same primary key value. The primary key is usually abbreviated as PK (primary key)

A foreign key is a key,
match the Primary Key in another table.
used to join two tables.
reference key.
A foreign key is a column or
combination of columns whose values
Sometimes also called

A foreign key is a key used to join two tables. Sometimes it is also called a reference key. A foreign key is a column or combination of columns whose values correspond to the Primary key in another table.

Practical work
- Build an example relational database
-Define the primary key for this database
-Explain your choice

Reflection:
-What difficulties did I face?
-What thing was easy for me?
-What thing I did not understand?
-Who would I thanked?