DBD::XBase(3pm)

1DBD::XBase(3)         User Contributed Perl Documentation        DBD::XBase(3)
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NAME

6       DBD::XBase - DBI driver for XBase compatible database files
7

SYNOPSIS

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();
15
16           my @data;
17           while (@data = $sth->fetchrow_array())
18                       { ## further processing }
19
20           $dbh->do('update table set name = ? where id = 45', {}, 'krtek');
21

DESCRIPTION

23       DBI compliant driver for module XBase. Please refer to DBI(3) documen‐
24       tation for how to actually use the module. In the connect call, specify
25       the directory containing the dbf files (and other, memo, etc.) as the
26       third part of the connect string. It defaults to the current directory.
27
28       Note that with dbf, there is no database server that the driver would
29       talk to. This DBD::XBase calls methods from XBase.pm module to read and
30       write the files on the disk directly, so any limitations and features
31       of XBase.pm apply to DBD::XBase as well. DBD::XBase basically adds SQL,
32       DBI compliant interface to XBase.pm.
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34       The DBD::XBase doesn't make use of index files at the moment. If you
35       really need indexed access, check XBase(3) for notes about support for
36       variour index types.
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SUPPORTED SQL COMMANDS

39       The SQL commands currently supported by DBD::XBase's prepare are:
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41       select
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43           select fields_or_expressions from table [ where condition ]
44                                               [ order by field ]
45
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" condi‐
48       tion 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 = ?
59
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".
65
66       Please note that you can only select from one table, joins are not sup‐
67       ported 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 func‐
73       tions I want to support. It's easy to write them in a couple of minutes
74       now the interface is there (check the XBase::SQL module if you want to
75       send a patch containing support for more), it's just that I do not
76       really need them and sometimes it's hard to tell what is usefull and
77       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
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87           delete from table [ where condition ]
88
89       The "where" condition is the same as for select. Examples:
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91           delete from jobs            ## emties the table
92           delete from jobs where companyid = "ISW"
93           delete from jobs where id < ?
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95       insert
96
97           insert into table [ ( fields ) ] values ( list of values )
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99       Here fields is a (optional) comma separated list of fields to set, list
100       of values is a list of constants to assign. If the fields are not spec‐
101       ified, sets the fields in the natural order of the table.  You can use
102       bind parameters in the list of values. Examples:
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104           insert into accounts (login, uid) values ("guest", 65534)
105           insert into accounts (login, uid) values (?, ?)
106           insert into passwd values ("user","*",4523,100,"Nice user",
107                                       "/home/user","/bin/bash")
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109       update
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111           update table set field = new value [ , set more fields ]
112                                               [ where condition ]
113
114       Example:
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116           update passwd set uid = 65534 where login = "guest"
117           update zvirata set name = "Jezek", age = 4 where id = 17
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119       Again, the value can also be specified as bind parameter.
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121           update zvirata set name = ?, age = ? where id = ?
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123       create table
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125           create table table name ( columns specification )
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127       Columns specification is a comma separated list of column names and
128       types. Example:
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130           create table rooms ( roomid int, cat char(10), balcony boolean )
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132       The allowed types are
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134           char num numeric int integer float boolean blob memo date time
135           datetime
136
137       Some of them are synonyms. They are of course converted to appropriate
138       XBase types.
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140       drop table
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142           drop table table name
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144       Example:
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146           drop table passwd
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ATTRIBUTES

149       Besides standard DBI attribudes, DBD::XBase supports database handle
150       attribute xbase_ignorememo:
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152               $dbh->{'xbase_ignorememo'} = 1;
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154       Setting it to 1 will cause subsequent tables to be opened while ignor‐
155       ing the memo files (dbt, fpt). So you can read dbf files for which you
156       don't have (you have lost them, for example) the memo files.  The memo
157       fields will come out as nulls.
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VERSION

160       0.240
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AUTHOR

163       (c) 1997--2003 Jan Pazdziora, adelton@fi.muni.cz,
164       http://www.fi.muni.cz/~adelton/ at Faculty of Informatics, Masaryk Uni‐
165       versity in Brno, Czech Republic
166