SAS Data Integration Interview Questions

1) What is the difference between unique key and primary key?

Ans : Unique key is one or more columns that can be used to uniquely identify a row in a table. A table can have one or more unique keys. Unique keys can contain null values. While on the other hand table can have only one primary key. One or more columns in a primary key cannot contain null values.

2) What do you mean by data staging area?

Ans. Staging area of the data warehouse is both the storage area and set of process commonly referred as extract transformation load. The data staging area is everything between the operational source systems and the data presentation area.

3) Describe about metadata object.

Ans : It is a set of attributes that describe a table, a server, a user and another resource on a network.

4) What is data governance?

Ans : It is the robust, reliable, repeatable and controlled process both at point of input and through subsequent downstream control checks. This process exists to manage updates of business rules to maintain a level of consistency.

5) What do you mean by exception reporting?

Ans : It is the reporting for data load completion to include any data issues.

6) What do you mean by fact table in dw ?

Ans : Fact table represents the subject oriented and the focus of analysis. it generally contains elements f analysis such as sales, cost, quantity sold etc. these attributes can be summed up or averaged in order to understand the particular aspects. Fact table can also be sum up as union of the dimension tables that allows the fact measures to be analyzed from different scenarios.

7) What is data dimension?

Ans : It is the definition of the customer, product and organization data to be held in central location and to be accessed by all the with governance around change. Common set of dimension are required to support all business views of data and self service reporting. Business view has the capability to segment customer, product and organization data across any dimension.

8) What is snow flake schema?

Ans : Snow flake schema is defined in which a single fact table is connected to multiple dimension tables. The dimension are structured to minimize update anomalies and to address single themes.

9) What is transformation in SAS data integration?

Ans : It is a metadata object which determines how to extract data, transform data and load data into data stores.

10) What is operational data and operational system?

Ans : Operational data is used as source data for a data warehouse. While operational system is one or more programs that provide source data for a data warehouse.