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NetSDS::DBI.3pm

NAME

NetSDS::DBI - DBI wrapper for NetSDS

SYNOPSIS

         use NetSDS::DBI;
 
         $dbh = NetSDS::DBI->new(
                 dsn    => 'dbi:Pg:dbname=test;host=127.0.0.1;port=5432',
                 login  => 'user',
                 passwd => 'topsecret',
         );
 
         print $db->call("select md5(?)", 'zuka')->fetchrow_hashref->{md5};
 
 

DESCRIPTION

"NetSDS::DBI" module provides wrapper around DBI module.

CLASS API

new(%params) - class constructor

     $dbh = NetSDS::DBI->new(
                 dsn    => 'dbi:Pg:dbname=test;host=127.0.0.1;port=5432',
                 login  => 'user',
                 passwd => 'topsecret',
         );
 
 

dbh() - DBI connection handler accessor

Returns: DBI object

This method provides accessor to DBI object and for low level access to database specific methods.

Example (access to specific method):

         my $quoted = $db->dbh->quote_identifier(undef, 'auth', 'services');
         # $quoted contains "auth"."services" now
 
 

call($sql, @bind_params) - prepare and execute SQL query

Method "call()" implements the following functionality:

         * check connection to DBMS and restore it
         * prepare chached SQL statement
         * execute statement with bind parameters
 
 

Parameters:

         * SQL query with placeholders
         * bind parameters
 
 

Return:

         * statement handler from DBI
 
 

Example:

         $sth = $dbh->call("select * from users");
         while (my $row = $sth->fetchrow_hashref()) {
                 print $row->{username};
         }
 
 

fetch_call($sql, @params) - call and fetch result

Paramters: SQL query, parameters

Returns: arrayref of records as hashrefs

Example:

         # SQL DDL script:
         # create table users (
         #       id serial,
         #       login varchar(32),
         #       passwd varchar(32)
         # );
 
         # Now we fetch all data to perl structure
         my $table_data = $db->fetch_call("select * from users");
 
         # Process this data
         foreach my $user (@{$table_data}) {
                 print "User ID: " . $user->{id};
                 print "Login: " . $user->{login};
         }
 
 

begin() - start transaction

commit() - commit transaction

rollback() - rollback transaction

quote() - quote SQL string

Example:

         # Encode $str to use in queries
         my $str = "some crazy' string; with (dangerous characters";
         $str = $db->quote($str);
 
 

INTERNAL METHODS

_add_sets() - add initial SQL query

Example:

     $obj->_add_sets("set search_path to myscheme");
     $obj->_add_sets("set client_encoding to 'UTF-8'");
 
 

_add_attrs() - add DBI handler attributes

     $self->_add_attrs(AutoCommit => 1);
 
 

_check_connection() - ping and reconnect

Internal method checking connection and implement reconnect

_connect() - connect to DBMS

Internal method starting connection to DBMS

EXAMPLES

samples/testdb.pl

SEE ALSO

DBI, DBD::Pg

TODO

1. Make module less PostgreSQL specific.

AUTHOR

Michael Bochkaryov <misha@rattler.kiev.ua>

LICENSE

Copyright (C) 2008-2009 Net Style Ltd.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA