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dBASE PLUS Downloadable Documentation
Download dbase 5 for windows for free. Development Tools downloads - dBASE PLUS by dBase, LLC and many more programs are available for instant and free download. DBASE IV v2.0 Ashton-Tate dBase was an early popular database management system for CP/M and MS-DOS. It was regarded as one of the killer applications for CP/M, and achieved good success. At the time of conception Ashton-Tate was a garage based company but quickly grew. 1 Valid only for dBASE version 5.x. Precision in dBASE III allows numbers with up to two-digit exponents and in dBASE IV numbers with up to three-digit exponents. Because numbers are stored as text, they are converted to numbers. If the number to convert does not fit in a field, unexplained results may occur. Stellar Phoenix DBF Recovery is a simple and user-friendly utility that allows safe recovery of DBX files created in dBase III, dBase IV, dBase V, and Microsoft Visual FoxPro 6.0 to 9.0. The software can efficiently recover all the lost or inaccessible database objects, such as table name, column name, column data types (Varchar, Varbinary. Dbase Iv free download - Caesar IV demo, Wing Commander IV demo, Settlers IV demo, and many more programs.
[accordion] [toggle title=”dBASE PLUS 12 Documentation” status=”open”] [/toggle] [toggle title=”dBASE PLUS 11 Documentation”] [/toggle] [toggle title=”dBASE PLUS 10 Documentation”] [/toggle] [toggle title=”dBASE PLUS 9 Documentation”] [/toggle] [toggle title=”dBASE PLUS 8 with ADO Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.8 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.70.3 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.70.2 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.62 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.61.5 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.61.4 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.6 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.5 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.1 / 2.21 Documentation”] [/toggle] [toggle title=”dBASE PLUS 2.01 Documentation”] [/toggle] [toggle title=”Visual dBASE 7.X Documentation”]- Visual dBASE 7.5 InstallShield UPDATE
Who needs to update? Users of Visual dBASE 7.5 who wish to use their licensed copy of InstallShield Express to deploy Visual dBASE 7.5 applications.
What does the update offer? If you have the version of InstallShield that shipped with Visual dBASE 7.01, or have upgraded to InstallShield Express 2.01, this download has the files needed to deploy your 7.5 applications, including what is needed to install the BDE version 5.10.
Update Procedure. Download the update package and unzip it to a temporary location. Read the file “ISX for 7.5 Documentation.doc” (you can use Wordpad if you do not have Word), and follow the instructions.
- Visual dBASE 7.0x Web Wizards BETA UPDATE
What does the update offer? This version of the Web Wizards fixes some bugs in the earlier versions, updates VdB 7.0x Professional to full CGI-Bin (usable with Microsoft IIS), a new version of VdB_CGI.exe that now supports the POST method in addition to GET method and has new, simplified code for OEM conversions.
- Microsoft Win32 SDK
If you need the Win32 Software Development Kit that accompanied Visual dBASE 7.0x, here it is. You’ll probably have time for a coffee break during the download.
- BDE 2.52 UPDATE (Visual dBASE 5.x)
This is the last update to the 16-bit version of the Borland Database Engine (BDE). Download and unzip to a temporary folder, and run the SETUP program.
- Visual dBASE 5.x DEPLOYER UPDATE
What does the update offer? This update enables the Visual dBASE 5.x Deployer to create deployment packages utilizing version 2.52 of the Borland Database Engine (BDE).
To install the update, unzip the downloaded package and copy the two .PAK files into your VISUALDBDEPLOY folder, overwriting the files of the same name.
- Visual dBASE 5.x DEPLOYER COPYRIGHT DATE KIT
What does the kit offer? This kit contains instructions and utilities to modify the default copyright date displayed by the Visual dBASE 5.x Deployer.
- Visual dBASE 5.x COMPONENT BUILDER
The Component Builder is used to help migrate your dBASE IV applications to Visual dBASE 5.x (5.5, 5.6, 5.7). This package includes all of the source files. Unzip the contents of this .zip file into your UTILS folder. You may wish to delete the file CB.PRO. Read CB.TXT for details.
- Visual dBASE 5.x INTRANET TOOLS
What does the Intranet Tools package offer? The Visual dBASE 5.x Intranet Tools provides a single solution for users of Visual dBASE 5.x looking to integrate databases with World Wide Web technology. The package is made up of two products:
Visual dBASE WebExperts, which allows you to point-and-click your way to dynamic CGI table-searching applications and easily transform tables into static HTML pages. DeltaPoint WebTools, which brings Visual dBASE users powerful class library utilities for interactive WWW database application development using CGI and HTML. Installation Procedure. Download the Intranet Tools package into a temporary directory, extract the files from WEBTOOLS.ZIP, and run SETUP.EXE. For more information, see README.TXT.
| Filename extension | |
|---|---|
| Developed by | dBase |
| Initial release | 1983; 37 years ago |
| Latest release | 7 |
| Website | dbase.com |
The .dbf file extension represents the dBase database file. The file type was introduced in 1983 with dBASE II. The file structure has evolved to include many features and capabilities. Several additional file types have been added, to support data storage and manipulation. The current .dbf file level is called Level 7. The .dbf format is supported by a number of database products.
Overview[edit]
The original dBASE database was known as Project Vulcan and was started by Wayne Ratliff in 1978. At the time the file that held the data was a simple table that could have data added, modified, deleted, or printed using the ASCII characters set.[1] As the product became more popular, the underlying file type .dbf was expanded, and additional files were added to increase the capabilities of the database system. Despite dBASE being an IDE (integrated development environment), a database system, a compiler, and a database application builder, the original .dbf file was still used for the actual data storage mechanism.
History of the file format[edit]
Project Vulcan – CP/M (Level 1) There is no publicly available information on the original layout. What is known is that it was a simple table which allowed adding, deleting, modifying, and outputting ASCII data. It was written for 8-bit machines that ran CP/M.
dBASE II – MS-DOS (Level 2) was the first major release by Ashton-Tate. It had many advancements beyond the simple table structures of Project Vulcan.[2]
- Still written for 8-bit computing
- Increased the number of fields from 16 to 32
- Introduced a SORT routine
- 16-bit version finally released in April 1983 (version 2.4)
dBASE III – MSDOS (Level 2sh) (version '1.0'), was released in June 1984. This was a fully 16-bit application. dBASE III's file format is a transitional step between dBASE II and dBASE III+.
dBASE III+ – MS-DOS (Level 3) was released in December 1985. dBASE III+ ushered the modern dBASE file format. It is incompatible with dBASE III's file format.
dBASE IV – MS-DOS (Level 4)
- 1.0 x322 Oct 1988
- 1.0 x55 Mar 1993 – dBASE Compiler
- 2.0 x12 Oct 1993 Includes fixes in dBASE IV v2.0 x16 above (not x17 i.e. not VLM compatible, dB5D exe's are compatible). It's also a new version that contain new features not in the V1.0 product:
- 32-bit generation
- Auto compiling and linking
- Smaller .EXE size
- Menu-driven user interface
- Linker can produce combined .DBO output
- Linker can produce a .MAP file
- Compiler supports alternate date formats
- command-line switches accept wildcards in file names.
dBASE V – MS-DOS (Level 5)
- 1.0 x46 Jun 1994
BDE – Borland Database Engine 2.52
This was the last update to the 16-bit version of the Borland Database Engine (BDE). Download and unzip to a temporary folder, and run the SETUP program.[3]
dBASE V – MS-Windows (Level 5)
- 5.5 b673 Jul 1995
dBASE 7 – MS-Windows (Level 7)
- 7.0 b1345 Dec 1997 Full 32 bit version for Win 95/NT
The Level 7 structure is the latest supported by dBASE and BDE.[4]
Level 7 brought many improvements. The maximum length for field names increased from 10 to 31 characters. Some new fields types were added, such as the auto-increment field,[5] which prevents creation of duplicate record numbers in the same table.
However, few third-party applications recognize level 7 tables.For .dbf files which are shared with such applications, the new features cannot be used.
BDE version 5.1.0
Significant improvements over the prior releases.[6] There are also some limitations with regards to what the BDE can handle.[7]
File format of Level 5 DOS dBASE[edit]
In dBASE V, a .dbf file consists of a header, the data records, and the end-of-file marker.
- The header contains information about the file, such as the number of records and the number of types of fields used in the records.
- The records contain the actual data.
- The end of the file is marked by a single byte, with value 0x1A.
File header[edit]
| Byte | Contents | Meaning |
|---|---|---|
| 0 | 1 byte | Valid dBASE for DOS file; bits 0–2 indicate version number, bit 3 indicates the presence of a dBASE for DOS memo file, bits 4–6 indicate the presence of a SQL table, bit 7 indicates the presence of any memo file (either dBASE m PLUS or dBASE for DOS) |
| 1–3 | 3 bytes | Date of last update; formatted as YYMMDD |
| 4–7 | 32-bit number | Number of records in the database file |
| 8–9 | 16-bit number | Number of bytes in the header |
| 10–11 | 16-bit number | Number of bytes in the record |
| 12–13 | 2 bytes | Reserved; fill with 0 |
| 14 | 1 byte | Flag indicating incomplete transaction[note 1] |
| 15 | 1 byte | Encryption flag[note 2] |
| 16–27 | 12 bytes | Reserved for dBASE for DOS in a multi-user environment |
| 28 | 1 byte | Production .mdx file flag; 1 if there is a production .mdx file, 0 if not |
| 29 | 1 byte | Language driver ID |
| 30–31 | 2 bytes | Reserved; fill with 0 |
| 32–n[note 3][note 4] | 32 bytes each | array of field descriptors (see below for layout of descriptors) |
| n + 1 | 1 byte | 0x0D as the field descriptor array terminator |
- ^The ISMARKEDO function checks this flag. BEGIN TRANSACTION sets it to 1, END TRANSACTION and ROLLBACK reset it to 0.
- ^If this flag is set to 1, the message Database encrypted appears. Changing this flag to 0 removes the message, but does not decrypt the file.
- ^The maximum number of fields is 255.
- ^n means the last byte in the field descriptor array. The array's size depends on the number of fields used in a database. n is equal to 31 + 32 * (number of fields).
Dbase Iv For Windows 10
Field descriptor array[edit]
| Byte | Contents | Meaning |
|---|---|---|
| 0–10 | 11 bytes | Field name in ASCII (zero-filled) |
| 11 | 1 byte | Field type. Allowed values: C, D, F, L, M, or N (see next table for meanings) |
| 12–15 | 4 bytes | Reserved |
| 16 | 1 byte | Field length in binary (maximum 254 (0xFE)). |
| 17 | 1 byte | Field decimal count in binary |
| 18–19 | 2 bytes | Work area ID |
| 20 | 1 byte | Example |
| 21–30 | 10 bytes | Reserved |
| 31 | 1 byte | Production MDX field flag; 1 if field has an index tag in the production MDX file, 0 if not |
Database records[edit]
Each record begins with a 1-byte 'deletion' flag. The byte's value is a space (0x20), if the record is active, or an asterisk (0x2A), if the record is deleted. Fields are packed into records without field separators or record terminators.
All field data is ASCII. Depending on the field's type, the application imposes further restrictions:
| Field type | Mnemonic | What it accepts |
|---|---|---|
| C | Character | Any ASCII text (padded with spaces up to the field's length) |
| D | Date | Numbers and a character to separate month, day, and year (stored internally as 8 digits in YYYYMMDD format) |
| F | Floating point | -, ., 0–9 (right justified, padded with whitespaces) |
| L | Logical | Y, y, N, n, T, t, F, f, or ? (when uninitialized) |
| M | Memo | Any ASCII text (stored internally as 10 digits representing a .dbt block number, right justified, padded with whitespaces) |
| N | Numeric | -, ., 0–9 (right justified, padded with whitespaces) |
Memo fields and the .DBT file[edit]
A memo (.DBT) file consists of blocks numbered sequentially (0,1,2, and so on). SET BLOCKSIZE determines the size of each block. The first block, block 0, is the memo file header.
Each memo field of each record in the .DBF file contains the number of the block (in ASCII) where the memo field begins. If the memo field contains no data, the .DBF file contains blanks (0x20) rather than a number.
When a memo field's content changes, its block number may also change. Absolute drift multiplier on clipping points. I.e. the memo gets relocated. In that case, the number in the .DBF file gets updated.
In dBASE III PLUS, the space consumed by deleted text in a memo field cannot be reused — the .DBT file size grows each time text is added, even if other text has been deleted. dBASE for DOS may reuse that space for new text. dBASE IQ PLUS always appended new text to the end of the .dbt file.
Other file types found in dBASE[edit]
dBASE defines many types of files. It also recognizes some operating system files and files from other products. The table below lists the most commonly used formats first. It was compiled from the documentation of dBASE III+, dBASE IV, and dBASE CLASSIC.[8]
| Extension | File content |
|---|---|
| .DBF | Database file |
| .DBK | Database backup file |
| .DBO | Command and procedure object file |
| .DBT | Database memo file |
| .DEF | Selector definition file |
| .DEM | Define statements for a CUA form |
| .DIF | Data Interchange Format, or VisiCalc file; used with APPEND FROM and COPY TO |
| .DOC | Documentation file; Applications Generator only |
| .ERR | Created if an error occurs during form generation, or if an unrecoverable error occurs |
| .FIL | Files list design object file |
| .EMO | Compiled format (.fmt) file |
| .FMT | Generated format file; from .scr file |
| .FNL | Report binary name list file |
| .FR3 | Renamed old dBASE HI report form (.frm) file |
| .ERG | Generated report form file; from .frm file |
| .FRM | Report form file |
| .FRO | Compiled report form (.ERG) file |
| .FW2, .FW3, .FW4 | Framework spreadsheet or database file; used for import and export |
| .GEN | Template file |
| .GRP | Windows group file for dBASE for DOS |
| .HLP | dBASE for DOS help files |
| .ICO | dBASE for DOS icon file under Windows |
| .INI | Windows-like INI file to save Label Designer and IDE state information. |
| .KEY | Keystroke macro library file |
| .LB3 | Renamed old dBASE III label form (.LBL) file |
| .LBG | Generated label form file; from .LBL file |
| .LBL | Label form file |
| .LBO | Compiled label form (.LBL) file |
| .LOG | Transaction log file |
| .LNL | Label binary name list file |
| .MBK | Multiple index backup file |
| .MDX | Multiple index file |
| .MEM | Memory file |
| .NDX | Single index file |
| .OVL | dBASE for DOS overlay file |
| PIF | Microsoft Windows file for non-Windows applications |
| .POP | Pop-up menu design object file; Applications Generator only |
| .PR2 | Printer driver file |
| .PRD | A file containing printer driver information for DBSETUP |
| .PRF | Print form file |
| .PRG | dBASE command or procedure file |
| .PRS | dBASE SQL command or procedure file |
| .PRT | Printer output file |
| .QBE | QBE query file |
| .QBO | Compiled QBE query (.QBE) file |
| .QRY | dBASE El query file |
| .RES | Resource file |
| .RPD | RapidFile file; used for import and export |
| .SC3 | Renamed old dBASE III screen (.SCR) file |
| .SCR | Screen file |
| .SNL | Screen binary name list file |
| .STR | Structure list design object file; Applications Generator only |
| .T44/.W44 | Intermediate work files; used by SORT and INDEX |
| .TBK | Database memo backup file |
| .TXT | ASCII text output file |
| .UPD | QBE update query file |
| .UPO | Compiled QBE update query (.UPD) file |
| .VAL | Values list design object file; Applications Generator only |
| .VMC | Configuration file; for Virtual Memory Manager (VMM) |
| .VUE | View file |
| .WIN | Logical window save file |
| .WKS, .WK1 | Lotus 1-2-3 file; used with APPEND FROM and COPY TO |
See also[edit]
References[edit]
- ^Powell, David B. (1984-02-07). 'From Basement To Boardroom'. PC Magazine. p. 131. Retrieved 24 October 2013.
- ^Powell, David B. (1984-02-07). 'From Basement to Boardroom'. PC Magazine: 131–135. Retrieved 2014-08-15.
- ^'dBASE Documentation Download - dBase, LLC'. Dbase.com. Retrieved 2014-08-15.
- ^'dBASE .DBF File Structure'. Dbase.com. Retrieved 2014-08-15.
- ^Jean-Pierre Martel. 'AutoIncrement Fields'. Dbase.com. Retrieved 2014-08-15.
- ^Jean-Pierre Martel. 'New BDE 5.1.0 and Visual dBASE 7.01'. Dbase.com. Retrieved 2014-08-15.
- ^[1]
- ^'dBASE Classic'. dBASE Classic. Retrieved 2014-08-15.
Further reading[edit]
Dbase Iv Software Free
- Ben Fry (18 December 2007). Visualizing Data: Exploring and Explaining Data with the Processing Environment. p. 325. ISBN9780596554729.
- Allen Kent, James G. Williams (5 October 1989). Encyclopedia of Microcomputers: Volume 4 - Computer-Related Applications: Computational Linguistics to dBase. p. 398. ISBN9780824727031.
External links[edit]
- FoxBase, dBASE III/IV file format specification (retrieved 6 August 2018)