10.2.1 Tables, records, and fields

• In relational databases, tables are used to store and organize related data
• Records in a table are also referred to as rows.
• A field in a table represents a specific attribute
• Match the key type with its definition:

  Primary Key ↔️ Uniquely identifies records in a table

  Foreign Key ↔️ Connects to primary key in another table
• What is a primary key used for in a relational database?

  Ensuring record uniqueness
• A table in a relational database is organized into rows and columns.
• A single row in a table is called a record
• What does a record in a relational database table represent?

  A single entity
• Each field in a record represents a specific attribute
• Fields in a relational database table can store different types of data, such as text, numbers, or dates.
• Match the key type with its purpose:

  Primary Key ↔️ Ensures each record is distinct

  Foreign Key ↔️ Establishes relationships between tables
• A primary key in a table cannot contain null values.
• What does the data type of a field define in a relational database?

  Type of data stored
• A field with the integer data type can store whole numbers without decimals
• In relational databases, data types define the type of data that can be stored in a field
• What type of data stores whole numbers without decimals?

  Integer
• What type of data stores numbers with decimals?

  Float
• The Text data type stores strings of characters.
• In the students table, the ID field is an integer
• Match the database term with its definition:

  Table ↔️ A collection of related data in rows and columns

  Record ↔️ A single row containing data for one entity

  Field ↔️ A column representing a specific attribute
• A table is a collection of related data in rows and columns
• What does a record in a relational database table represent?

  A single entity
• Fields define the structure of a table in relational databases.
• What is the primary purpose of a primary key in a table?

  Uniquely identify records
• A foreign key is a field in one table that references the primary key of another table
• In the students table, which field is the primary key?

  ID
• In the enrollments table, which field is the foreign key linking to the students table?

  StudentID
• Order the three main types of relationships in relational databases based on their complexity:

  1️⃣ One-to-One

  2️⃣ One-to-Many

  3️⃣ Many-to-Many
• In a one-to-many relationship, one record in table A can be related to multiple records in table B
• Which type of relationship requires a linking table with composite foreign keys?

  Many-to-Many