1DBD::XBase(3) User Contributed Perl Documentation DBD::XBase(3)
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6 DBD::XBase - DBI driver for XBase compatible database files
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9 use DBI;
10 my $dbh = DBI->connect("DBI:XBase:/directory/subdir")
11 or die $DBI::errstr;
12 my $sth = $dbh->prepare("select MSG from test where ID != 1")
13 or die $dbh->errstr();
14 $sth->execute() or die $sth->errstr();
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16 my @data;
17 while (@data = $sth->fetchrow_array())
18 { ## further processing }
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20 $dbh->do('update table set name = ? where id = 45', {}, 'krtek');
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23 DBI compliant driver for module XBase. Please refer to DBI(3)
24 documentation for how to actually use the module. In the connect call,
25 specify the directory containing the dbf files (and other, memo, etc.)
26 as the third part of the connect string. It defaults to the current
27 directory.
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29 Note that with dbf, there is no database server that the driver would
30 talk to. This DBD::XBase calls methods from XBase.pm module to read and
31 write the files on the disk directly, so any limitations and features
32 of XBase.pm apply to DBD::XBase as well. DBD::XBase basically adds SQL,
33 DBI compliant interface to XBase.pm.
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35 The DBD::XBase doesn't make use of index files at the moment. If you
36 really need indexed access, check XBase(3) for notes about support for
37 variour index types.
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40 The SQL commands currently supported by DBD::XBase's prepare are:
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42 select
43 select fields_or_expressions from table [ where condition ]
44 [ order by field ]
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46 Fields_or_expressions is a comma separated list of fields or arithmetic
47 expressions, or a "*" for all fields from the table. The "where"
48 condition specifies which rows will be returned, you can have arbitrary
49 arithmetic and boolean expression here, compare fields and constants
50 and use "and" and "or". Match using "like" is also supported. Examples:
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52 select * from salaries where name = "Smith"
53 select first,last from people where login = "ftp"
54 or uid = 1324
55 select id,first_name,last_name from employ
56 where last_name like 'Ki%' order by last_name
57 select id + 1, substr(name, 1, 10) from employ where age > 65
58 select id, name from employ where id = ?
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60 You can use bind parameters in the where clause, as the last example
61 shows. The actual value has to be supplied via bind_param or in the
62 call to execute or do, see DBI(3) for details. To check for NULL values
63 in the "where" expression, use "id is null" and "id is not null", not
64 "id == null".
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66 Please note that you can only select from one table, joins are not
67 supported and are not planned to be supported. If you need them, get a
68 real RDBMS (or send me a patch).
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70 In the arithmetic expressions you can use a couple of SQL functions --
71 currently supported are concat, substr (and substring), trim, ltrim and
72 rtrim, length. I do not have an exact idea of which and how many
73 functions I want to support. It's easy to write them in a couple of
74 minutes now the interface is there (check the XBase::SQL module if you
75 want to send a patch containing support for more), it's just that I do
76 not really need them and sometimes it's hard to tell what is usefull
77 and what is SQL92 compatible. Comment welcome.
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79 The select command may contain and order by clause. Only one column is
80 supported for sorting at the moment, patches are welcome.
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82 The group by clause is not supported (and I do not plan them), nor are
83 the aggregate functions.
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85 delete
86 delete from table [ where condition ]
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88 The "where" condition is the same as for select. Examples:
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90 delete from jobs ## emties the table
91 delete from jobs where companyid = "ISW"
92 delete from jobs where id < ?
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94 insert
95 insert into table [ ( fields ) ] values ( list of values )
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97 Here fields is a (optional) comma separated list of fields to set, list
98 of values is a list of constants to assign. If the fields are not
99 specified, sets the fields in the natural order of the table. You can
100 use bind parameters in the list of values. Examples:
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102 insert into accounts (login, uid) values ("guest", 65534)
103 insert into accounts (login, uid) values (?, ?)
104 insert into passwd values ("user","*",4523,100,"Nice user",
105 "/home/user","/bin/bash")
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107 update
108 update table set field = new value [ , set more fields ]
109 [ where condition ]
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111 Example:
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113 update passwd set uid = 65534 where login = "guest"
114 update zvirata set name = "Jezek", age = 4 where id = 17
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116 Again, the value can also be specified as bind parameter.
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118 update zvirata set name = ?, age = ? where id = ?
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120 create table
121 create table table name ( columns specification )
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123 Columns specification is a comma separated list of column names and
124 types. Example:
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126 create table rooms ( roomid int, cat char(10), balcony boolean )
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128 The allowed types are
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130 char num numeric int integer float boolean blob memo date time
131 datetime
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133 Some of them are synonyms. They are of course converted to appropriate
134 XBase types.
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136 drop table
137 drop table table name
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139 Example:
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141 drop table passwd
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144 Besides standard DBI attribudes, DBD::XBase supports database handle
145 attribute xbase_ignorememo:
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147 $dbh->{'xbase_ignorememo'} = 1;
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149 Setting it to 1 will cause subsequent tables to be opened while
150 ignoring the memo files (dbt, fpt). So you can read dbf files for which
151 you don't have (you have lost them, for example) the memo files. The
152 memo fields will come out as nulls.
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155 1.08
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158 http://www.adelton.com/perl/DBD-XBase/
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161 (c) 1997--2017 Jan Pazdziora.
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163 Contact the author at jpx dash perl at adelton dot com.
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166 perl(1); DBI(3), XBase(3); dbish(1)
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168 Translation into Japanese (older version) at
169 http://member.nifty.ne.jp/hippo2000/perltips/DBD/XBase.htm by Kawai
170 Takanori.
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174perl v5.32.1 2021-01-27 DBD::XBase(3)