Data Modeling - Star SchemaWhen relating a Fact Table with a Dimension Table, which of the following results in a Many-to-Many Relationship warning?

A Many-to-Many Relationship warning in a Star Schema data model typically occurs when a Fact Table is related to a Dimension Table in a way that one record in the Fact Table can correspond to multiple records in the Dimension Table, and vice versa. This is not ideal in a Star Schema because it can lead to ambiguity and confusion in data analysis.

Here are the steps that lead to a Many-to-Many Relationship warning:

1. Creation of Fact Table: A Fact Table is created with measures or metrics that are quantifiable and can be analyzed. This table usually contains foreign keys that correspond to primary keys in Dimension Tables.

2. Creation of Dimension Table: A Dimension Table is created with descriptive attributes that provide context to the measures in the Fact Table. This table usually contains a primary key that corresponds to a foreign key in the Fact Table.

3. Incorrect Relationship: A Many-to-Many Relationship warning occurs when a foreign key in the Fact Table can correspond to multiple primary keys in the Dimension Table, and a primary key in the Dimension Table can correspond to multiple foreign keys in the Fact Table. This is contrary to the typical one-to-many relationship in a Star Schema where one record in the Dimension Table corresponds to multiple records in the Fact Table, but not the other way around.

4. Warning: The data modeling tool or database management system will usually issue a warning when it detects this kind of relationship because it can lead to ambiguity and confusion in data analysis.

To resolve this warning, you would need to restructure your tables or relationships to ensure that they adhere to the one-to-many relationship principle of a Star Schema.