Latest Btrieve Interview Questions
What Is Btrieve?
Btrieve is a navigational database product
Based on Indexed Sequential Access Method(ISAM)
ISAM is a way of fast data retrieval
Btrieve retrieves one record at a time.
Transaction Operation is faster as there is little overhead with Btrieve Engine
Define A C Long Integer As A Key In Btrieve, When There Is No Long Data Type?
C long integer can be defined as a key in Btrieve by specifying the key as an integer. But the length need to be specified as four bytes.
How Can A Btrieve File Format Version Be Checked? In Other Words, How Can Someone Determine Whether A Btrieve File Is Stored In 5.x Or 6.x Format?
The process is as follows:
Run the BUTIL NLM version 6.x from the file server, which displays the version of file format after executing a STAT call.
No client BUTIL program is available to display this status
Another way is to check the version format of a Btrieve file by using DOS DEBUG utility
Type debug-d at DOS prompt.
The initial two bytes of the FCR will be set to FC when the file is stored in 6.x format.
Otherwise the bytes will be set to 0x00.
What Is Status 1015?
Prior to starting the application, if the environment variable SET BTRPARMSCHK=Y is specified, the status 1015 is returned.
Isolation of errors that are caused by passing invalid pointers to Btrieve is done by using this environment variable.
Once this variable is set, Btrieve performs the validation on pointer parameters that are passed in to READ/WRITE access on certain ranges.
Btrieve validates position block pointer on the range of 128 bytes, length pointer validates on two bytes and data buffer is validated on 255 bytes for key buffer
Explain About File Sharing?
Data available in a file can be shared by using Single Engine File Sharing and Multiple Engine File Sharing modes.
SEFS is allowed only to the clients to access the engine for altering databases.
MEFS allows multiple clients running under multiple engines for accessing the database.
Explain Error Codes Of Btrieve?
INVALID OPERATION –
The parameter of the operations of a call is invalid
I/O ERROR –
An error occurred during a disk read / write operation.
FILE NOT OPEN –
Any operation on the designated file can not be performed as the file is not open
KEY VALUE NOT FOUND –
The designated key value is not found in the index path
INVALID POSITIONING –
Each time the current position need to be established. This position is application for update / deletion of a record.
What Happens When You Use Netware Btrieve V5.x To Access An Btrieve File That Was Created In The V6.x Format?
When you attempt to open v56.x file with v5.x version, a status (I/O error) will be returned
Tell Me How To Convert A Bunch Of .btr And .lck Files To A Readable Sql?
Every Btrieve file and DDf has a owner of their creation.
Owner name can be used to read only access.
SET OWNER = command is used before utilizing SELECT statement.
.lck files are lock files and can not read them directly.
.btr files are DDF files.
The conversion can be made by using ODBC DSN that points to data and utilizes SSIS or DTS to export the data from.
Explain About System And User Transactions?
System transactions are non-transactional operations
System transactions are used for data recovery using MKDE.
User transactions are concurrent transactions.
User transaction might have lost when a recent transaction was rolled back
When a user transaction is rolled back, an option might be set which causes the MKDE to force the system transactions.
Explain Ddf Editor For Btrieve?
DDF editor allows to create the description of files
DDF is necessary to access Btrieve files through ODBC / OLE
Allows to
create / view / edit dictionary DDF
import and export data from ODBC data source
drag and drop / copy and paste the descriptions
rebuild files
search filtration data
How To Create Data Definition Files (.ddf) Files To Work With Third-party Products That Requires Them?
The .DDF file can be obtained in two ways;
The vendor of the product should be able to provide .DDF along with the software.
Or use Xtrieve PLUS,XQL or NetWare SQL for creating the .DDF file.
Can You Please Explain The Features Available In Btrieve Commander?
Btrieve Commander is a file viewer.
The primary view is named as Main View that lists the records one per line. A cursor vertical bar indicates the current record.
Record View :
It shows the records in the Main view and is limited
Calculate Totals :
This views allows to compute numeric fields of current record
Import and Export of Records :
The records in Btrieve can be imported from or exported to a Comma Separated Value files or the raw format that is utilized by the BUTIL’s save function.
Explain The Features Available In Btrieve Commander?
Btrieve Commander is a file viewer.
The primary view is named as Main View that lists the records one per line. A cursor vertical bar indicates the current record.
Record View :
It shows the records in the Main view and is limited
Calculate Totals :
This views allows to compute numeric fields of current record
Import and Export of Records :
The records in Btrieve can be imported from or exported to a Comma Separated Value files or the raw format that is utilized by the BUTIL’s save function.
How To Run Btrieve On Sft Iii Server?
The following engines are required to run Btrieve on SFT III server:
Btrieve.nlm on MSEngine
BSPXCOM.NLM on MSEngine
AFTER311.NLM on IOEngine
Btrieve is unaware of running SFT III Server
The I/O and mirroring will be taken care by OS
Will Brequest Works In An Os/2 V2.0 Dos Box?
Brequest will not properly function in multiple private DOS boxes. The system will halt.
Trap D occurs when Btrieve calls are made.
Can You Explain System And User Transactions?
System transactions are non-transactional operations
System transactions are used for data recovery using MKDE.
User transactions are concurrent transactions.
User transaction might have lost when a recent transaction was rolled back
When a user transaction is rolled back, an option might be set which causes the MKDE to force the system transactions.
How Do I Run Btrieve On Sft Iii Server?
The following engines are required to run Btrieve on SFT III server.
Btrieve.nlm on MSEngine
BSPXCOM.NLM on MSEngine
AFTER311.NLM on IOEngine
Btrieve is unaware of running SFT III Server
The I/O and mirroring will be taken care by OS
Tell Me Is It Necessary To Load Brequest If One Wants To Access The Btrieve Nlm From The Windows Environment?
Yes. First the DOS requester is loaded
Later windows is loaded
While the windows application is running,
The first window calls Btrieve to load and Btrieve Request Interface for windows.
Can Brebuild Rebuild Btrieve Files Created In The Btrieve V3.x Format, Or Is It Needed To Run Another Upgrade Utility First?
Rebuilding Btrieve files is possible using BREBUILD, if they have not extended across a volume.
CONVERT4 should be used after the files have been extended, for the purpose of translating Btrieve v3.x files to v4.x format
Later we can run BREBUILD.
Btireve v4.x and v5.x files can also be rebuild using BREBUILD.
What Is File Sharing?
Data available in a file can be shared by using Single Engine File Sharing and Multiple Engine File Sharing modes.
SEFS is allowed only to the clients to access the engine for altering databases.
MEFS allows multiple clients running under multiple engines for accessing the database.