Data Unveil Interview Questions and Answers

The interview questions are related to SQL and data manipulation.

• To fetch the last record of a column, you can use the ORDER BY clause with DESC keyword and LIMIT 1.

• Dense rank and rank are both ranking functions in SQL, but dense rank assigns consecutive rank numbers to rows, while rank leaves gaps in the ranking sequence.

• To fetch the end of 5 characters from a string column, you can use the RIGHT function in SQL.

I performed various types of data validation including format validation, completeness validation, and referential integrity validation.

• Format validation: Ensuring that the data is in the correct format as per the defined specifications. For example, validating that a date field is in the format 'YYYY-MM-DD'.

• Completeness validation: Checking if all the required fields are present and populated in the data. For example,...read more

Customers use data for various purposes such as analysis, decision-making, reporting, and personalization.

• Data is used for analysis to gain insights and identify patterns or trends.

• Data helps in decision-making by providing information and supporting evidence.

• Data is used for reporting to communicate information and track performance.

• Data enables personalization by tailoring products or services based on customer prefe...read more