Join this Blog for direct reference of any post into your inbox. To join just click on "Join this Site" under "Follower" then Login with your Email.*** DECLARATION: I Maintain this Blog for Helping Myself While at Work and Welcome any body Needing Help!!!.*** CAUTION: Using any of the script from this Blog may contain at Own Risk. These scripts May or May not have been Tested.***

Sunday, 24 June 2012

Interview Preparation SQL/PLSQL/D2K Part3

Which trigger are created when Master -Detail relation?
NON-ISOLATED (default): on check delete master,on clear details,on populate details
ISOLATED: on clear details,on populate details,
CASCADE: per-delete,on clear details,on populate details
Which system variables can be set by users?
What are object group?
An object group is a container for a group of objects. You define an object group when you want to  package related objects so you can copy or reference them in another module.
What are referenced objects?
Referencing allows you to create objects that inherit their functionality and appearance from other objects. Referencing an object is similar to copying an object, except that the resulting reference object maintains a  link to its source object. A reference object automatically inherits any changes that have been made to the source object when you open or regenerate the module that contains the reference object.
Can you store objects in library?
Referencing allows you to create objects that inherit their functionality and appearance from other objects. Referencing an object is similar to copying an object, except that the resulting reference object maintains a link to its source object. A reference object automatically inherits any changes that have been made to the source object when you open or regenerate the module that contains the reference object.
Is forms 4.5 object oriented tool? Why?
Yes , partially. 1) PROPERTY CLASS - inheritance property and 2) OVERLOADING : procedures and functions.
Can you issue DDL in forms?
Yes, but you have to use FORMS_DDL.
Restrictions: The statement you pass to FORMS_DDL may not contain bind variable references in the string, but the
Values of bind variables can be concatenated into the string before passing the result to FORMS_DDL. 
What is SECURE property?
Hides characters that the operator types into the text item.  This setting is typically used for password protection.
What are the types of triggers and how the sequence of firing in text item?
Triggers can be classified as Key Triggers, Mouse Triggers, and Navigational Triggers.
Key Triggers: Key Triggers are fired as a result of Key actions for Example Key-next-field, Key-up, Key-Down
Mouse Triggers: Mouse Triggers are fired as a result of the mouse navigation. For Example When-mouse-button-presed, when-mouse double clicked etc.
Navigational Triggers: These Triggers are fired as a result of Navigation. For Example Post-Text-item, Pre-text-item.
We also have event triggers like when-new-form-instance and when-new-block-instance. We cannot call restricted procedures like go_to(‘my_block.first_item’) in the Navigational triggers but can use them in the Key-next-item.
The Difference between Key-next and Post-Text is an very important question. The key-next is fired as a result of the key action while the post text  is fired as a result of the mouse movement. Key next will not fire unless there is a key event.
The sequence of firing in a text item is as follows:
    a) Pre - text
    b) When new item
    c) Key-next
    d) When validate
    e) Post text
Can you store pictures in database? How?
Yes , in long raw data type.
What are property classes? Can property classes have trigger?
Property class inheritance is a powerful feature that allows you to quickly define objects that conform to  your own interface and functionality standards. Property classes also allow you to make global changes to applications quickly.  By simply changing the definition of a property class, you can change the definition of all objects that inherit properties from that class.
Yes . All type of triggers .
If you have property class attached to an item and you have same trigger written for the item which will fire first?
Item level trigger fires , If item level trigger fires, property level trigger won't fire. Triggers at the lowest level are always given the first preference. The item level trigger fires first and then the block and then the Form level trigger.
What are record groups? Can record groups created at run-time?
A record group is an internal Oracle Forms data structure that has a column/row framework similar to a database table.  However, unlike database tables, record groups are separate objects that belong to the form module in which they are defined.  A record group can have an unlimited number of columns of type CHAR, LONG, NUMBER, or DATE provided that the total number of columns does not exceed 64K.  Record group column names cannot exceed 30 characters. Programmatically, record groups can be used whenever the functionality offered by a two-dimensional array of multiple data types is desirable.
The types of record group are:
Query Record Group: A query record group is a record group that has an associated SELECT statement. The columns in a query record group derive their default names, data types, and lengths from the database  columns referenced in the SELECT statement.  The records in a query record group are the rows retrieved by the query associated with that record group.
Non-query Record Group: A non-query record group is a group that does not have an associated query, but whose structure and values can be modified programmatically at runtime.
Static Record Group: A static record group is not associated with a query; rather, you define its structure and row values at design time, and they remain fixed at runtime.
What is ALERT?
An ALERT is a modal window that displays a message notifiying operator of some application condition.
Can a button have icon and label at the same time?
What is mouse navigate property of button?
When Mouse Navigate is True (the default), Oracle Forms performs standard navigation to move the focus to the item when the operator activates the item with the mouse. When Mouse Navigate is set to False, Oracle Forms does not perform navigation (and the resulting validation) to move to the item when an operator activates the item with the mouse.
 Forms run inside the MDI application window. This property is useful for calling a form from another one.
What are timers? When the “when-timer-expired” does not fire?
The When-Timer-Expired trigger can not fire during trigger, navigation, or transaction processing.
Can object group have a block?
Yes , object group can have block as well as program units.
How many types of canvases are there.
There are 2 main types of canvases called as Content and Stack Canvas. Content canvas is the default and the one that is used mostly for giving the base effect. It’s like a plate on which we add items and stacked canvas is used for giving 3 dimensional effect. The other canvas is Tab type window, Toolbar Canvas, Horizontal and Vertical Toolbar.
What are user-exits?
It invokes 3GL programs.
Can you pass values to-and-fro from foreign function? How?
Yes . You obtain a return value from a foreign function by assigning the return value to an Oracle Forms variable or item.  Make sure that the Oracle Forms variable or item is the same data type as the return value from the foreign function.
After assigning an Oracle Forms variable or item value to a PL/SQL variable, pass the PL/SQL variable as a parameter value in the PL/SQL interface of the foreign function.  The PL/SQL variable that is passed as a parameter must be a valid PL/SQL data type; it must also be the appropriate parameter type as defined in the PL/SQL interface. 
What is IAPXTB structure?
The entries of  Pro * C and user exits and the form which simulate the proc or user_exit are stored in IAPXTB  table in d/b.
Can you call WIN-SDK through user exits?
Does user exits supports DLL on MS-Windows?
What is path setting for DLL?
Make sure you include the name of the DLL in the FORMS45_USEREXIT variable of the ORACLE.INI file, or rename the DLL to F45XTB.DLL.  If you rename the DLL to F45XTB.DLL, replace the existing F45XTB.DLL in the \ORAWIN\BIN directory with the new F45XTB.DLL.
How is mapping of name of DLL and function done?
The DLL can be created using the Visual C++ / Visual Basic Tools and then the DLL is put in the path that is defined the registry.
What is precompiler?
It is similar to C precompiler directives.
Can you connect to non - oracle data source? How?
Yes . 
What are key-mode and locking mode properties? Level?
Key Mode: Specifies how oracle forms uniquely identify rows in the database. This is property includes for application that will run against Non-Oracle data sources. Key setting: Unique (default.), Dateable, N-updateable.
Locking mode: Specifies when Oracle Forms should attempt to obtain database locks on rows that correspond to queried records in the form: a) Immediate b) delayed
What are savepoint mode and cursor mode properties? Level?
Specifies whether Oracle Forms should issue savepoints during a session. This property is included primarily  for applications that will run against non-ORACLE data sources.   For applications that will run against ORACLE, use the default setting.
Cursor mode - define cursor state across transaction
What is transactional trigger property?
Identifies a block as transactional control block. i.e. non - database block that oracle forms should manage  as transactional block.(Non-Oracle data source) default - FALSE.
What is OLE automation?
OLE automation allows an OLE server application to expose a set of commands and functions that can be invoked from an OLE container application.  OLE automation provides a way for an OLE container application  to use the features of an OLE server application to manipulate an OLE object from the OLE container environment. (FORMS_OLE)
What does invoke built-in do?
This procedure invokes a method.
   (object obj_type,
    method VARCHAR2,
    list   list_type := 0);
Parameters details:
Object: Is an OLE2 Automation Object.
Method: Is a method (procedure) of the OLE2 object.
List: Is the name of an argument list assigned to the OLE2.CREATE_ARGLIST function.
What are OPEN_FORM, CALL_FORM, and NEW_FORM difference?
CALL_FORM: It calls the other form but parent remains active, when called form completes the operation,  it releases lock and control goes back to the calling form. When you call a form, Oracle Forms issues a savepoint for the called form.  If the CLEAR_FORM function causes a rollback when the called form is current, Oracle Forms rolls back uncommitted changes to this savepoint.
OPEN_FORM: When you call a form, Oracle Forms issues a savepoint for the called form.  If the CLEAR_FORM function causes a rollback when the called form is current, Oracle Forms rolls back uncommitted changes to this savepoint.
NEW_FORM:  Exits the current form and enters the indicated form.  The calling form is terminated as the parent form.  If the calling form had been called by a higher form, Oracle Forms keeps the higher call active and treats it as a call to the new form.  Oracle Forms releases memory (such as database cursors) that the terminated form was using. Oracle Forms runs the new form with the same Runform options as the parent form.  If the parent form was a called form, Oracle Forms runs the new form with the same options as the parent form.
What does 2 modes of isolation for form module
Specifies whether or not transactions in a session will be serializable.  If Isolation Mode has the value Serializable, the end user sees a consistent view of the database for the entire length of the transaction, regardless of updates committed by other users from other sessions. If the end user queries and changes a row, and a second user updates and commits the same row from another session, the first user sees Oracle error (ORA-08177: Cannot serialize access.).
Read committed (default)
The serialize works in conjunction with the block's locking property set as delayed. The basic idea behind serialize is that the user sees a consistent set of rows throughout the entire runtime session, inspite of any row being changed by another user of different session.
This is mainly useful when the application access a very large databases and very few users use the appln so that the chances of users waiting for locked records is less.
What is call form stack?
When successive forms are loaded via the CALL_FORM procedure, the resulting module hierarchy is known  as the call form stack.
Can you port applications across the platforms? How?
Yes we can port applications across platforms. Consider the form developed in a windows system. The form would be generated in UNIX system by using f45gen my_form.fmb scott/tiger
What is a visual attribute?
Visual attributes are the font, color, and pattern properties that you set for form and menu objects that appear in your application's interface.
Difference between VAT and Property Class?
VAT is a Named visual attributes define only font, color, and pattern attributes; property classes can contain these and  any other properties.
You can change the appearance of objects at runtime by changing the named visual attribute programmatically; property class assignment cannot be changed programmatically. When an object is inheriting from both a property class and a named visual attribute, the named visual attribute settings take precedence, and any visual attribute properties in the class are ignored.
Which trigger related to mouse?
When-Mouse-Click, When-Mouse-Double Click, When-Mouse-Down, When-Mouse-Enter, When-Mouse-Leave, When-Mouse-Move, When-Mouse-Up
What is Current record attribute property?
Specifies the named visual attribute used when an item is part of the current record. Current Record Attribute is frequently used at the block level to display the current row in a multi-record. If you define an item-level Current Record Attribute, you can display a pre-determined item in a special color when it is part of the current record, but you cannot dynamically highlight the current item, as the input focus  changes. 
Can you change VAT at run time?
Yes. You can programmatically change an object's named visual attribute setting to change the font, color,  and pattern of the object at runtime.
Can you set default font in forms?
Yes. Change windows registry (regedit). Set form45_font to the desired font.
Can you have OLE objects in forms?
Can you have VBX and OCX controls in forms?
What are the types of windows (Window style)?
Specifies whether the window is a Document window or a Dialog window.
What is OLE Activation style property?
Specifies the event that will activate the OLE containing item.
Can you change the mouse pointer? How?
Yes. Specifies the mouse cursor style.  Use this property to dynamically change the shape of the cursor.
How to use 2 different tables at runtime In my query or Main Block
Set_block_Property built in Query_Data_source_name, but you have to give alias to the items of block and Select statement you have to do same.


Post a Comment