Describe the use of PL/SQL table?

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: SELECT *FROM Employees WHERE EmpName like ?M%?

Correct Answer: 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

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

Correct Answer: Too_many_rows No_Data_Found Zero_Error

Correct Answer: Cursor_Already_Open, Invalid_Cursor

Correct Answer: By use of %ISOPEN status variable

Correct Answer: Use the DBMS_OUTPUT package Another possible method is to use the SHOW ERROR command

Correct Answer: Similarity: Both WHERE and HAVING Clause filters out records based on one or more conditions Difference: WHERE Clause can only be applied to a static non-aggregated column whereas HAVING is needed for aggregated columns