MQdb::Database(3pm) User Contributed Perl Documentation MQdb::Database(3pm)
NAME - MQdb::Database
DESCRIPTION
Generalized handle on an DBI database handle. Used to provide an instance which holds connection information and allows a higher level
get_connection/ disconnect logic that persists above the specific DBI connections. Also provides a real object for use with the rest of the
toolkit.
SUMMARY
MQdb::Database provides the foundation of the MappedQuery system. Databases are primarily specified with a URL format. The URL format
includes specification of a driver so this single method can select among the supported DBD drivers. Currently the system supports MYSQL,
Oracle, and SQLite. The URL also allows the system to provide the foundation for doing federation of persisted objects. Each DBObject
contains a pointer to the Database instance where it is stored. With the database URL and internal database ID, each object is defined in
a global space.
Attributes of MQdb::Database
driver : mysql, oracle, sqlite (default mysql)
user : username if the database requires
password : password if the database requires
host : hostname of the database server machine
port : IP port of the database if required
(mysql default is 3306)
dbname : database/schema name on the database server
for sqlite, this is the database file
Example URLS
mysql://<user>:<pass>@<host>:<port>/<database_name>
mysql://<host>:<port>/<database_name>
mysql://<user>@<host>:<port>/<database_name>
mysql://<host>/<database_name>
oracle://<user>:<pass>@/<database_name>
oracle://<user>:<pass>@<host>:<port>/<database_name>
sqlite:///<database_file>
CONTACT
Jessica Severin <jessica.severin@gmail.com>
LICENSE
* Software License Agreement (BSD License)
* MappedQueryDB [MQdb] toolkit
* copyright (c) 2006-2009 Jessica Severin
* All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Jessica Severin nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
APPENDIX
The rest of the documentation details each of the object methods. Internal methods are usually preceded with a _
new
Description: instance creation method
Parameter : a hash reference of options same as attribute methods
Returntype : instance of this Class (subclass)
Exceptions : none
new
Description: instance creation method
Returntype : instance of this Class (subclass)
Exceptions : none
init
Description: initialization method which subclasses can extend
Returntype : $self
Exceptions : subclass dependent
new_from_url
Description: primary instance creation method
Parameter : a string in URL format
Returntype : instance of MQdb::Database
Examples : my $db = MQdb::Database->new_from_url("mysql://<user>:<pass>@<host>:<port>/<database_name>");
e.g. mysql://<host>:<port>/<database_name>
e.g. mysql://<user>@<host>:<port>/<database_name>
e.g. mysql://<host>/<database_name>
e.g. sqlite:///<database_file>
my $class = shift;
Exceptions : none
copy
Description: makes a copy of the database configuration.
New instance will have its own database connection
Returntype : instance of MQdb::Database
dbc
Description: connects to database and returns a DBI connection
Returntype : DBI database handle
Exceptions : none
disconnect
Description: disconnects handle from database, but retains object and
all information so that it can be reconnected again
at a later time.
Returntype : none
Exceptions : none
full_url
Description: returns the URL of this database with user and password
Returntype : string
Exceptions : none
url
Description: returns URL of this database but without user:password
used for global referencing and federation systems
Returntype : string
Exceptions : none
xml
Description: returns XML of this database but without user:password
used for global referencing and federation systems
Returntype : string
Exceptions : none
execute_sql
Description : executes SQL statement with external parameters and placeholders
Example : $db->execute_sql("insert into table1(id, value) values(?,?)", $id, $value);
Parameter[1] : sql statement string
Parameter[2..] : optional parameters for the SQL statement
Returntype : none
Exceptions : none
do_sql
Description : executes SQL statement with "do" and no external parameters
Example : $db->do_sql("insert into table1(id, value) values(null,'hello world');");
Parameter : sql statement string with no external parameters
Returntype : none
Exceptions : none
fetch_col_value
Arg(1) : $sql (string of SQL statement with place holders)
Arg (2...) : optional parameters to map to the placehodlers within the SQL
Example : $value = $self->fetch_col_value($db, "select some_column from my_table where id=?", $id);
Description: General purpose function to allow fetching of a single column from a single row.
Returntype : scalar value
Exceptions : none
Caller : within subclasses to easy development
perl v5.10.0 2009-05-30 MQdb::Database(3pm)