An example of working with DBF on c. How to open DBF? Removing entries in the DBF file

You can use a multiple algorithm for the part of the file rows:

Unloading to DBF file

Stages of unloading to the DBF file:

1. Creating an XBASE object;
2. Specifying the encoding (if not specified, the ANSI encoding will be used);
3. Field description;
4. Creating a file;
5. Cycle with adding and filling rows;
6. Closing the file.

Consider this process on the example:

When specifying an encoding, uses the type of encodingXBase, which can take two values:

• Ansi. - Windows format;
• OEM. - DOS format.

Adding a new field when describing the structure has a syntax

The following types are available:

• "N" - a number;
• "S" - line;
• "D" - date;
• "L" - Boolewo;
• "F" - similar to "N" - a number.

The field length is mandatory for the types of "n", "f" and "s" fields.

Working with indexes

Together with the DBF file, an index file can be used, which may contain information about one or more index. The presence of indexes makes it possible to use the search, and not just the consistent enumeration of all the file rows.

While creating index file. You should set:

• List of indexes;
• Path save the index file (at step 4 of unloading).

An example of creating an index file:

The procedure for adding a new index has a syntax:

To use indexes when reading from the DBF file, follows:

• Specify the path to the index file (at step 2 of downloads);
• Set the current index.

An example of opening a DBF file using an index file:

Attention!

When you open the DBF file, positioning occurs on the first entry in the file. The first entry in the file does not match the first entry in the index. In this regard, when using indexes before consistently bypass the rows, it is necessary to be signed on the first line of the index. This can be done by the first () method (), for example:

To search, one of two functions can be used:

• To find (< Ключ>, < Режим >) ;
• Found Point (< Режим >) .

As a result of the work of both functions, the value with the buvene type is returned (a record with specified conditions or not). In the case of a successful search, the current pointer is set at the found line. As a search mode, one of the values \u200b\u200bcan be used:

• «>=»;
• «>»;
• «<=»;
• «<«.

Consider the search in the DBF file on the examples:

Removing entries in the DBF file

Delete recording is made by the Delete method ():

But when using this method, the recording is not deleted from the file permanently, it is assigned a reference mark. When crossing rows marked to remove records are skipped. If you need to get around the entire file, including marked to delete recording, you must assign the value of the truth to the property. Displayed XBASE object. You can find a removal entry or not using the recording function (). To remove the removal, the restore () method is used.

To directly delete marked records, it is used to compress () method:

If you need to delete all entries in the file directly, you can use the Clear File () method:

Loading from DBF with ADO

ADO technology can be used to work with DBF files. ADO drivers are part of the Windows operating system and install them additionally.

Consider a sample code for reading from the DBF file according to ADO technology:

The example of the connection line "Provider \u003d Microsoft.jet.oledb.4.0; Data Source \u003d" D: \\ "; Extended Properties \u003d DBASE III. In this line:

• Provider is a driver used;
• Data Source - the path where the DBF file is located. The path is indicated with an accuracy of the catalog. The file name is used as a table name in queries;
• Extended Properties - In the case of accessing DBF files is a mandatory parameter. You can specify the file format

Attention!

When reading the specified method, the default encoding is OEM. In order to change the encoding on ANSI, you must assign the HKEY_LOCAL_MACHINE \\ SOFTWARE \\ WOW6432NODE \\ MICROSOPT \\ JET \\ DATACODEPAGE parameter in the Windows registry.

DBF format tables are known from the distant 1980. Since then, DBase format has evolved, developed, DBASE II, DBASE III and DBASE IV appeared, many popular programs working with databases are developed to date, in which the DBF format tables are used to this day. The DBF table format is quite old, but it continues to be used to create both large and ambitious and small projects, DBF tables are used for educational purposes, for dating and studying basic knowledge and presentation of the organization databases. DBFnavigator is a free program for viewing and editing the DBF format tables, a simple and convenient utility.

With the DBFnavigator program, you can open and view the DBF tables, edit tables - change, add and delete records. Using DBFnavigator, you can change the table structure, add, change and delete the table fields, compress the DBF tables to clean them from remote records (garbage collection), change the Windows-\u003e DOS table encoding and vice versa. In the program, you can sort the table entry, copy the records and individual fields, display the rows of the printing table, perform the search and apply to view the filter table records, change the options for opening DBF files.

Screenshots of the DBFnavigator program

DBF Viewer 2000 ® - App for viewing and editing DBF all types - Clipper, Dbase, FoxPro, Visual Foxpro, Visual Dbase.

The program performs various actions: requests, deleting duplicates or export to various formats - faster than you expect!

DBF editor dynamically creates visual forms based on the DBF file structure for editing and queries. The program also allows you to view and edit the Memo fields of the following formats: DBASE III, DBASE IV, FOXPRO, VFP and DBASE LEVEL 7.

The fullness program supports the use of a command line for the following: Import, Export, Deleting Duplicate Records or Replacing Data in DBF files. Works independently of various DBMS - all you need to view and edit a DBF file to install the application!

Why DBF Viewer 2000
unique?

Simple and intuitive interface

The application interface is quite simple and convenient, allows you to save a lot of time with everyday work.

Convenient modification of the DBF file structure in DBF Viewer 2000

You can add, delete, rename, change the order of fields and optimize the structure of DBF files.

Import data from various formats with DBF Viewer 2000

DBF Viewer 2000 Allows you to import data from the following formats: TXT, CSV, Excel (XLS, XLSX), DBF and PARADOX. Import data can be performed with preview or from a command line.

DBF Viewer 2000 offers extended export opportunities

The application allows you to export DBF files in Excel (XLS, XLSX), CSV, TXT, SQL, SDF, XML, HTML, PRG, and MS SQL, MySQL, Oracle, PostgreSQL scripts.

DBF Viewer 2000 helps remove duplicates

Removing duplicate records is easy as 1-2-3.

Works on all platforms

DBF Viewer 2000 launches on all versions of Windows from 95 to XP, Vista, 7/8/10 and Server Editions (32/64-bit)

The most common problem, due to which users cannot open this file, is an incorrectly assigned program. To fix it in Windows, you need to right-click on the file, in the context menu, bring the mouse to "Open Using" item, and select the Select Program item drop-down menu. As a result, you will see a list of installed programs on your computer, and you can choose a suitable one. We also recommend checking the box opposite the item "Use this application for all DBF files".

Another problem with which our users also occur quite often - the DBF file is damaged. Such a situation may arise in cases of cases. For example: the file was downloaded not fully as a result of server error, the file was damaged initially, etc. To eliminate this problem, use one of the recommendations:

• Try finding the desired file in another source on the Internet. You may be lucky to find a more suitable version. Google search example: "File FileType: DBF". Just replace the word "file" to the name you need;
• Ask you to send you the source file again, it may have been damaged during transmission;

The DBF format (Data Base File) was introduced to the use of Ashton-Tate in 1980, in the first DBMS of the DBASE database management systems family - dBASE II.

Open data format and the popularity of the original system led to the appearance of many different DBMS analogues, such as FOXPRO, DBFast, Xbase ++ and others. At the same time, the developers made various changes to the basic format associated with functionality (adding new data types, changing the header structure or table field structure, etc.).

The absence of any rigid standardization and similar changes have affected the lack of guarantees that the program being developed can correctly perform the read / write operation with any DBF file. However, basic compatibility is preserved between different DBF formats.

The DBF file consists of 2 partitions: the title and directly the data table itself. The title contains general information about the DBF file: the file structure, the number of entries used by the DBF version, the amount of memory occupied by title and table, etc. The composition of the header structure is different in various versions of the format.

The end of the file is marked with an EOF (End of File).

To speed up working with DBF files, it is possible to use index files in which the key field values \u200b\u200bare listed (or a set of key fields if the multi index file) and identifiers of the corresponding records.

In 1C, work with DBF files can be carried out in several ways:

• XBase object;
• Programming interface

XBASE object

The XBase object provides the ability to work with DBF format databases using the built-in 1C: Enterprise.

This object provides access to the collection of fields and DBF-table indexes, allows you to perform any actions on the data (creating new and read existing tables, add, adjusting and deleting records).

For each DBF file with which you want to create a separate XBASE object.

Programming Interface ADO.

ADO (ActiveX Data Objects) is a programming interface for data access that allows you to obtain data from various sources.

Basic ADO objects allowing to perform manipulations with a DBF file:

With the full list of objects and their properties can be found in MSDN.

Connection - an object directly providing access to a DBF file

Recordset - object representing a set of records (strings) of data table

Command - an object providing execution of commands or SQL queries