Trigger allows us to execute a batch of SQL code when an insert, update or delete command is executed against a specific table Triggers are special types of stored procedures that are defined to execute automatically in place of or after data modifications They can be executed automatically on the insert, delete and update operation
Correct Answer: Recursive query can be create in SQL using stored procedure but you can also use CTE (Common table expression) It might be also worth asking about performance as CTE is not always very fast
2. Mention the difference between clustered and a non-clustered index?
Correct Answer: - A clustered index is a special type of index that reorders the way records in the table are physically stored Therefore table can have only one clustered index - A non clustered index is a special type of index in which the logical order of the index does not match the physical stored order of the rows on disk The leaf node of a non clustered index does not consist of the data pages Instead, the leaf nodes contain index rows
3. Which command using Query Analyzer will give you the version of SQL server and operating system?
Correct Answer: SQL Server agent plays an important role in the day-to-day tasks of a database administrator (DBA) Its purpose is to ease the implementation of tasks for the DBA, with its full- function scheduling engine, which allows you to schedule your own jobs and scripts
Correct Answer: This command is used when a large processing of data has occurred If any large amount of deletions, any modifications, or Bulk Copy into the tables has occurred, it has to update the indexes to take these changes into account UPDATE_STATISTICS updates the indexes on these tables accordingly
6. Write an SQL Query to find employees whose name starts with an ?M??
Correct Answer: An SQL statement is a string of characters that conforms to the syntax and format specified in the international standard A query is a statement that returns a record-set
Correct Answer: PL/SQL tables are scalar arrays that can be referenced by a binary digit They can be used to store values for later queries and calculations