Schema Design Questions

Snowflake Schemas don't use fact tables.

Star Schemas have more joins.

Star Schemas are used for real-time analytics.

Snowflake Schemas normalize dimension tables.

Choosing appropriate data types for columns

Storing redundant data in multiple columns

Defining primary keys to uniquely identify each row

Using descriptive names for tables and columns

It prevents deletion of records in the parent table if there are matching records in the child table.

It automatically deletes matching records in the child table when a record in the parent table is deleted.

It has no impact on the child table when a record in the parent table is deleted.

It sets the foreign key values in the child table to NULL when a record in the parent table is deleted.

Lack of a primary key

Transitive dependencies between non-key attributes

Partial dependencies on the primary key

Repeating groups of data

To speed up data retrieval operations

To improve data security

To enforce data integrity constraints

To reduce disk space consumption

1NF is the most desirable normal form for all databases

Normalization guarantees perfect database design

A table in 3NF is also automatically in 2NF and 1NF

2NF automatically implies 3NF

Define a new data type for a column.

Establish a link between two tables based on a common column.

Create a primary key for a related table.

Enforce data validation rules on a column.

A relationship between two different tables.

A column header describing the data type.

A specific attribute or characteristic of an entity.

A unique record or instance within the table.

queries are optimized for performance.

data is backed up regularly.

all columns in a table have unique values.

relationships between tables remain consistent.

Data Normalization

Data Warehousing

Data Validation

Data Integrity