DBF
¶ ↑
DBF
is a small, fast Ruby library for reading dBase, xBase, Clipper, and FoxPro database files.
-
Project page: github.com/infused/dbf
-
API Documentation: rubydoc.info/github/infused/dbf
-
Report bugs: github.com/infused/dbf/issues
-
Questions: Email keithm@infused.org and put
DBF
somewhere in the subject line -
Change log: github.com/infused/dbf/blob/master/CHANGELOG.md
NOTE: Beginning with version 4.3 we have dropped support for Ruby 3.0 and earlier.
NOTE: Beginning with version 4 we have dropped support for Ruby 2.0, 2.1, 2.2, and 2.3. If you need support for these older Rubies, please use 3.0.x (github.com/infused.org/dbf/tree/3_stable)
NOTE: Beginning with version 3 we have dropped support for Ruby 1.8 and 1.9. If you need support for older Rubies, please use 2.0.x (github.com/infused/dbf/tree/2_stable)
Compatibility¶ ↑
DBF
is tested to work with the following versions of Ruby:
-
Ruby 3.1.x, 3.2.x, 3.3.x
Installation¶ ↑
Install the gem manually:
gem install dbf
Or add to your Gemfile:
gem 'dbf'
Basic Usage¶ ↑
Open a DBF
file using a path:
require 'dbf' widgets = DBF::Table.new("widgets.dbf")
Open a DBF
file using an IO object:
data = File.open('widgets.dbf') widgets = DBF::Table.new(data)
Open a DBF
by passing in raw data (wrap the raw data with StringIO):
widgets = DBF::Table.new(StringIO.new('raw binary data'))
Enumerate all records
widgets.each do |record| puts record.name puts record.email end
Find a single record
widget = widgets.find(6)
Note that find() will return nil if the requested record has been deleted and not yet pruned from the database.
The value for an attribute can be accessed via element reference in several ways.
widget.slot_number # underscored field name as method widget["SlotNumber"] # original field name in dbf file widget['slot_number'] # underscored field name string widget[:slot_number] # underscored field name symbol
Get a hash of all attributes. The keys are the original column names.
widget.attributes # => {"Name" => "Thing1 | SlotNumber" => 1}
Search for records using a simple hash format. Multiple search criteria are ANDed. Use the block form if the resulting record set is too big. Otherwise, all records are loaded into memory.
# find all records with slot_number equal to s42 widgets.find(:all, slot_number: 's42') do |widget| # the record will be nil if deleted, but not yet pruned from the database if widget puts widget.serial_number end end # find the first record with slot_number equal to s42 widgets.find :first, slot_number: 's42' # find record number 10 widgets.find(10)
Enumeration¶ ↑
DBF::Table
is a Ruby Enumerable, so you get several traversal, search, and sort methods for free. For example, let’s get only records created before January 1st, 2015:
widgets.select { |w| w.created_date < Date.new(2015, 1, 1) }
Or custom sorting:
widgets.sort_by { |w| w.created_date }
Encodings (Code Pages)¶ ↑
dBase supports encoding non-english characters with different character sets. Unfortunately, the character set used may not be set explicitly. In that case, you will have to specify it manually. For example, if you know the dbf file is encoded with ‘Russian OEM’:
table = DBF::Table.new('dbf/books.dbf', nil, 'cp866')
Code Page | Encoding | Description |
---|---|---|
01 | cp437 | U.S. MS–DOS |
02 | cp850 | International MS–DOS |
03 | cp1252 | Windows ANSI |
08 | cp865 | Danish OEM |
09 | cp437 | Dutch OEM |
0a | cp850 | Dutch OEM* |
0b | cp437 | Finnish OEM |
0d | cp437 | French OEM |
0e | cp850 | French OEM* |
0f | cp437 | German OEM |
10 | cp850 | German OEM* |
11 | cp437 | Italian OEM |
12 | cp850 | Italian OEM* |
13 | cp932 | Japanese Shift-JIS |
14 | cp850 | Spanish OEM* |
15 | cp437 | Swedish OEM |
16 | cp850 | Swedish OEM* |
17 | cp865 | Norwegian OEM |
18 | cp437 | Spanish OEM |
19 | cp437 | English OEM (Britain) |
1a | cp850 | English OEM (Britain)* |
1b | cp437 | English OEM (U.S.) |
1c | cp863 | French OEM (Canada) |
1d | cp850 | French OEM* |
1f | cp852 | Czech OEM |
22 | cp852 | Hungarian OEM |
23 | cp852 | Polish OEM |
24 | cp860 | Portuguese OEM |
25 | cp850 | Portuguese OEM* |
26 | cp866 | Russian OEM |
37 | cp850 | English OEM (U.S.)* |
40 | cp852 | Romanian OEM |
4d | cp936 | Chinese GBK (PRC) |
4e | cp949 | Korean (ANSI/OEM) |
4f | cp950 | Chinese Big5 (Taiwan) |
50 | cp874 | Thai (ANSI/OEM) |
57 | cp1252 | ANSI |
58 | cp1252 | Western European ANSI |
59 | cp1252 | Spanish ANSI |
64 | cp852 | Eastern European MS–DOS |
65 | cp866 | Russian MS–DOS |
66 | cp865 | Nordic MS–DOS |
67 | cp861 | Icelandic MS–DOS |
6a | cp737 | Greek MS–DOS (437G) |
6b | cp857 | Turkish MS–DOS |
6c | cp863 | French–Canadian MS–DOS |
78 | cp950 | Taiwan Big 5 |
79 | cp949 | Hangul (Wansung) |
7a | cp936 | PRC GBK |
7b | cp932 | Japanese Shift-JIS |
7c | cp874 | Thai Windows/MS–DOS |
86 | cp737 | Greek OEM |
87 | cp852 | Slovenian OEM |
88 | cp857 | Turkish OEM |
c8 | cp1250 | Eastern European Windows |
c9 | cp1251 | Russian Windows |
ca | cp1254 | Turkish Windows |
cb | cp1253 | Greek Windows |
cc | cp1257 | Baltic Windows |
Migrating to ActiveRecord¶ ↑
An example of migrating a DBF
book table to ActiveRecord using a migration:
require 'dbf' class Book < ActiveRecord::Base; end class CreateBooks < ActiveRecord::Migration def self.up table = DBF::Table.new('db/dbf/books.dbf') eval(table.schema) Book.reset_column_information table.each do |record| Book.create(title: record.title, author: record.author) end end def self.down drop_table :books end end
If you have initialized the DBF::Table
with raw data, you will need to set the exported table name manually:
table.name = 'my_table_name'
Migrating to Sequel¶ ↑
An example of migrating a DBF
book table to Sequel using a migration:
require 'dbf' class Book < Sequel::Model; end Sequel.migration do up do table = DBF::Table.new('db/dbf/books.dbf') eval(table.schema(:sequel, true)) # passing true to limit output to create_table() only Book.reset_column_information table.each do |record| Book.create(title: record.title, author: record.author) end end down do drop_table(:books) end end
If you have initialized the DBF::Table
with raw data, you will need to set the exported table name manually:
table.name = 'my_table_name'
Command-line utility¶ ↑
A small command-line utility called dbf is installed with the gem.
$ dbf -h usage: dbf [-h|-s|-a] filename -h = print this message -v = print the version number -s = print summary information -a = create an ActiveRecord::Schema -r = create a Sequel Migration -c = export as CSV
Create an executable ActiveRecord schema:
dbf -a books.dbf > books_schema.rb
Create an executable Sequel schema:
dbf -r books.dbf > migrate/001_create_books.rb
Dump all records to a CSV file:
dbf -c books.dbf > books.csv
Reading a Visual Foxpro database (v8, v9)¶ ↑
A special Database::Foxpro class is available to read Visual Foxpro container files (file with .dbc extension). When using this class, long field names are supported, and tables can be referenced without using names.
require 'dbf' contacts = DBF::Database::Foxpro.new('contact_database.dbc').contacts my_contact = contacts.record(1).spouses_interests
dBase version compatibility¶ ↑
The basic dBase data types are generally supported well. Support for the advanced data types in dBase V and FoxPro are still experimental or not supported. If you have insight into how any of the unsupported data types are implemented, please open an issue on Github. FoxBase/dBase II files are not supported at this time.
Supported data types by dBase version¶ ↑
Version | Description | C | N | L | D | M | F | B | G | P | Y | T | I | V | X | @ | O | + |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
02 | FoxBase | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - | - |
03 | dBase III without memo file | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - | - |
04 | dBase IV without memo file | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - | - |
05 | dBase V without memo file | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - | - |
07 | Visual Objects 1.x | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - | - |
30 | Visual FoxPro | Y | Y | Y | Y | Y | Y | Y | Y | N | Y | N | Y | N | N | N | N | - |
31 | Visual FoxPro with AutoIncrement | Y | Y | Y | Y | Y | Y | Y | Y | N | Y | N | Y | N | N | N | N | N |
32 | Visual FoxPro with field type Varchar or Varbinary | Y | Y | Y | Y | Y | Y | Y | Y | N | Y | N | Y | N | N | N | N | N |
7b | dBase IV with memo file | Y | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - |
83 | dBase III with memo file | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - |
87 | Visual Objects 1.x with memo file | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | - | - | - | - |
8b | dBase IV with memo file | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | N | - | - | - |
8e | dBase IV with SQL table | Y | Y | Y | Y | Y | - | - | - | - | - | - | - | - | N | - | - | - |
f5 | FoxPro with memo file | Y | Y | Y | Y | Y | Y | Y | Y | N | Y | N | Y | N | N | N | N | N |
fb | FoxPro without memo file | Y | Y | Y | Y | - | Y | Y | Y | N | Y | N | Y | N | N | N | N | N |
Data type descriptions
-
C = Character
-
N = Number
-
L = Logical
-
D = Date
-
M = Memo
-
F = Float
-
B = Binary
-
G = General
-
P = Picture
-
Y = Currency
-
T = DateTime
-
I = Integer
-
V = VariField
-
X = SQL compat
-
@ = Timestamp
-
O = Double
-
= Autoincrement
-
Limitations¶ ↑
-
DBF
is read-only -
Index files are not utilized
License¶ ↑
Copyright © 2006-2024 Keith Morrison <keithm@infused.org>
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.