Centric Consulting Interview Questions, Process, and Tips

Truncate removes all data from a table while delete removes specific rows.

• Truncate is faster than delete as it doesn't log individual row deletions

• Truncate cannot be rolled back while delete can be

• Truncate resets the identity of the table while delete doesn't

• Truncate doesn't fire triggers while delete does

To delete duplicate rows, we can use the DISTINCT keyword or GROUP BY clause in SQL.

• Use the DISTINCT keyword to select unique rows from a table.

• Use the GROUP BY clause to group rows with the same values and select only one row from each group.

• Use the HAVING clause with GROUP BY to filter out groups with more than one row.

• In Informatica, use the Sorter transformation to sort the data and then use the Aggregator transfor...read more

Star and snowflake are two types of database schema used in data warehousing.

• Star schema is simpler and easier to understand.

• Snowflake schema is more normalized and reduces data redundancy.

• Star schema is better for simple queries and reporting.

• Snowflake schema is better for complex queries and analysis.

• Star schema has fewer tables and is faster for querying.

• Snowflake schema has more tables and is slower for querying.

• St...read more