10+ Perfetti Van Melle Interview Questions and Answers

Types of Trigger in Oracle forms and their sequence of firing.

• Types of triggers include Key Triggers, Mouse Triggers, and Timer Triggers.

• Key Triggers fire when a key is pressed or released.

• Mouse Triggers fire when the mouse is clicked or moved.

• Timer Triggers fire at a specified interval.

• The sequence of trigger firing is Pre-Form, Pre-Block, Pre-Record, Post-Record, Post-Block, and Post-Form.

Explanation of differences between PK & UK, Case & Decode, Procedure & Function, Cursor & Refcursor.

• PK (Primary Key) is a unique identifier for a record in a table, while UK (Unique Key) ensures uniqueness but allows null values.

• Case and Decode are conditional statements used to manipulate data based on certain conditions.

• Procedure and Function are both database objects used to perform a specific task, but Function returns a value while Procedure does not.

• Cursor and Refcursor...read more

A placeholder column is a column that is used to reserve space for a future column in an Oracle report.

• Placeholder columns are used to ensure that the layout of a report remains consistent even if data is missing.

• They are typically used when a report is designed to display a fixed number of columns, but the data source may not always contain data for all of those columns.

• Placeholder columns can be added to a report by selecting the Placeholder Column option in the Report Wiza...read more

Collection in Oracle is a group of elements of the same data type. Types include VARRAY, Nested Table, and Associative Array.

• VARRAY is a fixed-size array that can hold a varying number of elements up to the specified limit.

• Nested Table is a dynamic array with no fixed size that can be stored in a database column.

• Associative Array is a collection of key-value pairs where the key is unique and used to access the corresponding value.

A DB block is a unit of data storage in Oracle Forms that contains multiple rows of data from a database table.

• DB blocks are used to improve performance by reducing the number of times a form needs to access the database.

• Each DB block contains a fixed number of rows, which can be configured in the form's block properties.

• When a form needs to display data from a table, it reads one or more DB blocks into memory.

• If a form needs to update data, it writes the changes back to the ...read more

Method overloading is having multiple methods in the same class with the same name but different parameters. Method overriding is redefining a method in a subclass with the same name and parameters as in the superclass.

• Method overloading allows a class to have multiple methods with the same name but different parameters.

• Method overriding occurs in a subclass when a method has the same name and parameters as in its superclass.

• Method overloading is resolved at compile time base...read more

Canvas, LOV, and List button are UI components used in Oracle Forms.

• Canvas is a visual container used to display data or graphics.

• LOV (List of Values) is a drop-down list used to select a value from a predefined list.

• List button is a button used to display a list of values in a pop-up window.

• These components are commonly used in Oracle Forms to create user-friendly interfaces.

Dual is a special one-row, one-column table in Oracle DB.

• Dual is used to perform calculations or execute functions without selecting from a table.

• It is often used to generate a sequence of numbers or to concatenate strings.

• For example, SELECT 1+1 FROM dual; will return 2.

• Dual is automatically created by Oracle and is always available in every Oracle database.

The static keyword in programming is used to declare variables, methods, or classes that belong to the class itself rather than instances of the class.

• Static variables are shared among all instances of a class

• Static methods can be called without creating an instance of the class

• Static classes cannot be instantiated and are used for grouping related methods together

Call_Form is a built-in Oracle Forms procedure used to call another form from the current form.

• Call_Form is used to open a new form while keeping the current form open.

• It can be used to pass parameters between forms.

• The called form can be modal or non-modal.

• The called form can be in the same application or a different one.

• Syntax: Call_Form('form_name', [mode], [hide], [no_replace], [query_only], [params])