Top 25 Dbase Interview Questions You Must Prepare 19.Mar.2024

To export records, select menu "File/Save As". You can select the fields to be exported and specify their order. DBF Viewer allows you export records with memo to Excel(xls, xlsx), CSV, TXT, XML, SQL and HTML file formats.

Users have found that newer versions of the Microsoft dBASE ODBC Driver (version 3.0 or newer) can be used to read level 7 tables in newer versions of Crystal Reports. (Even though it is not 'officially' reported as such.)

Therefore you should be able to use the Microsoft dBASE ODBC Driver to connect to data through Crystal Reports.

Before creating a DSN for your Dbase tables, please ensure that your ODBC Driver is 3.0 or higher.

You can easy add, rename, and delete fields in your dbf files by using table structure designer.

dBase was one of the first database management systems for microcomputers, and the most successful in its day. The dBase system includes the core database engine, a query system, a forms engine, and a programming language that ties all of these components together.

  1. Click Start -> Control panel -> Administrative tools ->Data sources (ODBC) 
  2. Click ‘Add’, Select ‘Microsoft dBase Driver’ from the driver list, Click ‘Finish’. 
  3. A new dialog window will appear, give a name to Datasource name, eg “Dbase” 
  4. Now check off ‘Use Current Directory’, Click on ‘Select Directory’ and provide the path where your dbase file resides. 
  5. Click ‘OK’, Click ‘OK’, Click ‘OK’. 
  6. Now open Crystal Reports.
  7. Click ‘Blank Report ‘, you will see a ‘Database Expert’ dialog box. 
  8. double click on ‘ODBC(RDO)’ 
  9. A ‘ODBC(RDO)’ dialog box will appear, select your DSN from the list. 
  10. Click ‘Finish’ 
  11. Now you will see the ‘Table’ under your DSN name. 
  12. Now select tables you want for reporting. 
  13. Click ‘Finish’.

DBF files were originally used in dBase II and continued through to dBase Version IV. The DBF file format originated by Ashton-Tate, but is understood by Act!, Clipper,FoxPro, Arago, Wordtech, xBase, and similar database ordatabase-related products. DBF files can also be opened by Microsoft Excel and Microsoft Access.

Data Execution Prevention is a mechanism built into some CPU's to check whether or not the data within a particular chunk of memory is tagged as code or as data before allowing any address in that chunk of memory to be used by the CPU to execute any instructions.

DBF Recovery empowers its users with the ability to recover a damaged database back to its pristine condition without needing the expertise to accomplish such a task or requiring the additional expense of hired recovery services. When the program runs, you see a simple interface with two main fields. Select the file for recovery in the first field and the folder for the output in the second.

As an added option, you can choose to recover deleted records in the database. Once everything is set, you click on the Start button. DBF Repair Tool does the rest. It repairs the headers and data structures in an automatic process that involves no interaction with the user. After all you may not want to sit around and watch the process. With DBF Recovery, you'll truly have a lean, mean DBF repairing machine without functional fluff.

Use built-in import wizard for importing data from xls, txt, csv, xlsx, xml, dbf file formats.

The .cdx, .mdx, .ndx, .ntx index files contain and maintain pointers to records in the table (.dbf) file and is organized according to the index key values. An index file is separate from but associated with a .dbf file. So, you should open a .dbf file firstly and then associated index file(s) if needed.

Unlike .cdx/.mdx files that open automatically when the associated table is opened, you must open a .ndx/.ntx file explicitly using program's Index Manager dialog box (File->Index manager menu item).

Index files are only relevant for searching in the DBF - you really don't need them (i.e. you CAN read the .dbf data file without the index file). Removing the index file might break you application though.

To edit a memo field, select record in the list and double-click on the "Memo". Memo editor allows you view, edit, print and export to text file.

To edit a dbf file, select record in the list and double-click or press Enter

DBF is a file format typically used by database software. DBF stands for DataBase File. DBF files were originally used in dBase II and continued through to dBase Version IV.

DBase history can be traced back to 1978, when it was created by Wayne Ratliff and initially named the "Vulcan." In the 1980s, Ashton-Tate purchased Vulcan and marketed it as DBase II, which is considered to be the first DBase version.

dBASE Plus, beginning with version 2.61.4, supports running application exe's that have been code signed.

Code Signing is a method of identifying who the publisher of an executable file is and ensuring that the file has not been altered since publication.

It works by adding a digital signature to the end of an executable file which can then be checked at runtime for its authenticity.

A digital signature consists of a digital certificate along with a publisher's public key that has been issued by a certification authority (such as VeriSign, Thawte, or Comodo). A part of the digital certificate is encrypted using the publisher's private key.

With connection to an iSeries driver via ODBC….

  • In the ODBC Administrator - choose to modify the DSN.
  • Under the 'Catalog' tab of the 'iSeries access for Windows ODBC setup' dialog- there is a setting called 'Enable search patterns' 
  • If this setting is not checked then the tables will not be visible in the 'Databases and Tables' list in dQuery. 
  • If this setting is checked (enabled) then you should see the tables.

Launch Microsoft Excel. Press "Ctrl-O" or click on the "File" tab and choose "Open." Set the "Files of Type" drop-down menu in the Open dialog box to "dBase Files (.dbf)." Navigate to the location of the database document you want to open.

The XP manifest file is used to have your form objects look like the new XP common controls. Because of this, pushbuttons; rectangles; notebooks and possibly other objects have their color settings all or partially overwridden.

The pushbutton has a property called systemTheme which when set to false (the default is true) will ignore the manifest file and use the old common controls thereby allowing the color settings to show.

Open Access: Click on the Start button, select Programs, Microsoft Office, then click on Microsoft Access. Select blank database. The "File New Database" window will appear. Select Desktop (or directory where you saved the .dbf file) in the "Save in" box at the top of the window.

The business customers can use the visual report designer (with a complete set of layout and design controls), to design highly formatted, interactive, and professional looking reports. Reports can be exported and repurposed to the electronic formats used by most end users (e.g. PDF and Excel).

Most of the old XBASE commands that run on VFP will also run on dBASE except in cases where FoxPro diverged from the dBASE syntax or invented new syntax.

However, the newer object oriented features in VFP, such as Forms, Entryfields, PushButton's etc are very different from the equivalent dBASE features.

At this time there are no conversion tools available to convert from VFP to dBASE Plus.

However, we have compiled 3 text files that show how Visual FoxPro commands map to dBASE Plus. 

  1. VFP2dBMatchingCmd.txt - contains a list of VFP commands whose names map to exact or nearly exact dBASE Plus equivalents
  2. VFP2dBEquivCmd.txt - contains a list of VFP commands that can be handled differently in dBASE Plus. The second column shows how to look for the dBASE Plus equivalent.
  3. VFP2dBNoMatch.txt - contains a list of VFP commands that do not have a close equivalent in dBASE Plus.

Some of these items can be replicated in dBASE by using add-on libraries or by custom coding.

Log on as system admin and change the Data Execution Prevention on for "All programs and services except those I select" and then add the name of each executable to the list. For example ... plusrun.exe, plus.exe, dQuery.exe., (or for the installers plus-setup.exe or dqsa-setup.exe)

Steps :

  • Right-click on "My Computer" and select the Properties page. 
  • On the Properties page, select the "Advanced" tab, and click on the "Settings" button in the "Performance" section. 
  • On the Performance Options page, select the "Data Execution Prevention" tab. 
  • Use the "Add" button on this page to add the affected services to the opt out list. 
  • Click "OK" on each of the pages when finished and reboot the system.

Instructions to open a DBF file in Excel :

Below are basic instructions for opening a DBF file in Excel. For more detailed instructions, view Instructions for Opening a Database File in Excel (DOC; 1MB).

Right click on pubschls.dbf link and select "Save target as." When the "SAVE AS" Window appears, fill in the three boxes as directed below:    

Save in: Desktop or directory of choice
File Name: pubschls.dbf  
Save as Type: All
Close the "Download Complete" Window after the file is finished downloading.
Open Excel.
Select File, Open.

In the "Look In" drop down box, select the desktop or directory in which you saved the file and in the Files of Type drop down box, select: All Files (*.*).

Double click on the file name.The .dbf file will now open in Excel.

Start -> Control panel -> Administrative tools ->Data sources (ODBC) -> ‘Driver’ Tab.

 From the ODBC Administrator (the same dialog that configures your datasource),

  • select the "Drivers" tab.
  • Highlight the "Microsoft dBase Driver"
  • The version column lists the current version as a four part number. Leading zeros in each part are not significant.