Powerbuilder interview questions
PowerBuilder IDE crash problem solving
Valid Answers in no particular order:
- Make sure that all of the PBL’s are included in the library search path.
- Make sure PBL’s are listed in the proper order in library search path.
- Try regenerating the PBL’s or finding a project object and doing a full build.
- Determine ancestor objects and see if they compile and/or open.
- Make sure you have the right version of the application object, you might have a generic application object because some shops don’t put the application object under source control and you may not be using intended custom transaction or other system object.
- Try rebooting and/or restarting PB.
- Try connecting to the database if one is used in the application.
- Edit the source, rather than using the window painter and try to locate the problem area.
- Edit the source, rather than using the window painter and comment problem code until window compiles. Open window using IDE and determine why commented code fails (e.g. missing objects and/or ancestors)
- Set up a database profile in the PowerBuilder IDE if there isn’t one (new PB install) already, even if it is an unrelated ODBC connection to an Excel file, sometimes PB gets cranky if there isn’t a db connection and an object has embedded SQL.
- If there is version control, try turning it off to isolate that issue.
- Re-install PowerBuilder and the proper updates from the Sybase website.
- After completing basic troubleshooting maybe see if a co-worker is able to open the window to rule out a bad PB installation or PC related issue.
- Look at the window source (via edit source) and see if there are Active X controls that might be added to the window but are not available on your PC.
Question 2 Goals:
The goal for this question is to determine the developers ability to problem solve. I would expect a seasoned developer to come up with at least three of these right off the bat. If you have others to add to the list please add a comment; and I will add them to the list!
(For Developers on Recent Versions) Recent PowerBuilder Functions or Features
What are some of the new functions or features that were introduced to PowerBuilder since you’ve been using PowerBuilder. This question hasn’t made it to the common canned interview lists yet and it is a good way to see if the developer has used recent versions of PowerBuilder.
Possible Answers:
A.) Function “SaveAsFormattedText” was added in Version 10 of PowerBuilder. The SaveAsFormattedText method for DataWindow controls and DataWindow objects has the same function as SaveAsAscii, but lets you select the encoding of the file to which you save. Like SaveAsAscii, this function also mirrors more closely what the user sees on the screen with the added benefit of allowing save in different file encodings. The function also displays column headers with real column header text, and displays computed fields.
B.) SaveAsAscii was introduced in PowerBuilder 6, it is a cross between the SaveAs (Text!) function and the SaveAs (HTMLTable!) function with additional arguments. It mirrors more closely what the user sees on the screen. Arguments allow the user to control how contents are separated and delimited in the ASCII file. PowerBuilder assigns a cell for each DataWindow object (which can include computed columns and group totals).
C.) Unicode support is a big one that most newer developers will know about. It was added in version 10 and anyone performing migrations from older versions to version 10 or newer had to deal with the move to Unicode. The source code in PowerBuilder 10 PBLs is encoded in UTF-16LE. UTF-16LE is a Unicode encoding scheme that serializes a UTF-16 code unit sequence as a byte sequence in little-endian format, in which multiple-byte numerical values are stored with the least significant byte first. PBLs developed in earlier versions of PowerBuilder contain source code in ANSI or DBCS format. When you migrate applications to PowerBuilder 10, each PBL is first migrated to the new version of PowerBuilder, as in previous releases. Then PowerBuilder converts the source code from ANSI or DBCS to Unicode, performs a full build, and saves the source code back to the same file.
- The FromAnsi, FromUnicode, ToAnsi, and ToUnicode functions were added to help with the Unicode migration, however are removed from a future versions of PowerBuilder and the migration tool replaces them with the appropriate syntax of the Blob or String function.
D.) The PFC was removed from PowerBuilder Installation program in version 10, and made available on the PowerBuilder CodeXchange Web site for public use and modification. The PFC was included on the CD, however not part of the installation options.
E). The SetFilter has a new parameter added in PB11 that allows changing the sort from dictionary to ascii. The sort parameter is /s and is used in the SetFilter expression, and when used the sorting is dictionary.
F.) The Rich Text Edit controls, 3D Graph Styles and PNG Support were added in PB version 11.5. Support for function calls on .NET primitive and enumerated types was also added in PB11.5. Also notable were native database connectivity to MS SQL Server 2008 and Oracle 11.
G.) WPF Targets, Complete .NET Interoperability were added in PB Version 12. Version 12 was the first delivered with two IDE’s the classic and .NET versions.
H.) The dot notation was added as an option to PowerBuilder in more recent versions (approx version 7) that can be used in place of some common datawindow object functions such as dwCreate, dwModify, GetItemString, GetItemNumber, etc..
I.) Database connection pooling was added in Version 12, allowing sharing of a database connection.
Database Connectivity
Connecting to the database is one of those things that was always challenging when you didn’t know PB, but mindless once you do have experience. I would ask a developer which databases they have connected to with PowerBuilder. And depending on the answers, ask for clarifications, such as exactly what steps would you take to create a new database connection for Oracle? A good developer should be able to talk with authority about their experiences in this area. creat
If you want to drill into it deeper maybe ask them which client libraries they had to use to connect to the database.
Oracle: OCI or newer Instant Client
SQL Server: DB Lib and/or CT Lib
FAQ
What is Buffer in PowerBuilder?
When data is retrieved from the databse by using retrieve() function, it is retrieved into the Primary Buffer and it is the content of this buffer that are displayed in the datawindow. Powerbuilder always displays the data in datawindow control from the Primary Buffer.
What is the latest version of PowerBuilder?
