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NAME

DBIx::Class::Storage::DBI::Oracle::Generic - Oracle Support for DBIx::Class

SYNOPSIS

# In your result (table) classes
use base 'DBIx::Class::Core';
__PACKAGE__->add_columns({ id => { sequence => 'mysequence', auto_nextval => 1 } });
__PACKAGE__->set_primary_key('id');

# Somewhere in your Code
# add some data to a table with a hierarchical relationship
$schema->resultset('Person')->create ({
      firstname => 'foo',
      lastname => 'bar',
      children => [
          {
              firstname => 'child1',
              lastname => 'bar',
              children => [
                  {
                      firstname => 'grandchild',
                      lastname => 'bar',
                  }
              ],
          },
          {
              firstname => 'child2',
              lastname => 'bar',
          },
      ],
  });

# select from the hierarchical relationship
my $rs = $schema->resultset('Person')->search({},
  {
    'start_with' => { 'firstname' => 'foo', 'lastname' => 'bar' },
    'connect_by' => { 'parentid' => { '-prior' => { -ident => 'personid' } },
    'order_siblings_by' => { -asc => 'name' },
  };
);

# this will select the whole tree starting from person "foo bar", creating
# following query:
# SELECT
#     me.persionid me.firstname, me.lastname, me.parentid
# FROM
#     person me
# START WITH
#     firstname = 'foo' and lastname = 'bar'
# CONNECT BY
#     parentid = prior personid
# ORDER SIBLINGS BY
#     firstname ASC

DESCRIPTION

This class implements base Oracle support. The subclass DBIx::Class::Storage::DBI::Oracle::WhereJoins is for (+) joins in Oracle versions before 9.0.

METHODS

get_autoinc_seq

Returns the sequence name for an autoincrement column

datetime_parser_type

This sets the proper DateTime::Format module for use with DBIx::Class::InflateColumn::DateTime.

connect_call_datetime_setup

Used as:

on_connect_call => 'datetime_setup'

In connect_info to set the session nls date, and timestamp values for use with DBIx::Class::InflateColumn::DateTime and the necessary environment variables for DateTime::Format::Oracle, which is used by it.

Maximum allowable precision is used, unless the environment variables have already been set.

These are the defaults used:

$ENV{NLS_DATE_FORMAT}         ||= 'YYYY-MM-DD HH24:MI:SS';
$ENV{NLS_TIMESTAMP_FORMAT}    ||= 'YYYY-MM-DD HH24:MI:SS.FF';
$ENV{NLS_TIMESTAMP_TZ_FORMAT} ||= 'YYYY-MM-DD HH24:MI:SS.FF TZHTZM';

To get more than second precision with DBIx::Class::InflateColumn::DateTime for your timestamps, use something like this:

use Time::HiRes 'time';
my $ts = DateTime->from_epoch(epoch => time);

relname_to_table_alias

DBIx::Class uses DBIx::Class::Relationship names as table aliases in queries.

Unfortunately, Oracle doesn't support identifiers over 30 chars in length, so the DBIx::Class::Relationship name is shortened and appended with half of an MD5 hash.

See "relname_to_table_alias" in DBIx::Class::Storage::DBI.

with_deferred_fk_checks

Runs a coderef between:

alter session set constraints = deferred
...
alter session set constraints = immediate

to defer foreign key checks.

Constraints must be declared DEFERRABLE for this to work.

ATTRIBUTES

Following additional attributes can be used in resultsets.

connect_by or connect_by_nocycle

Value: \%connect_by

A hashref of conditions used to specify the relationship between parent rows and child rows of the hierarchy.

connect_by => { parentid => 'prior personid' }

# adds a connect by statement to the query:
# SELECT
#     me.persionid me.firstname, me.lastname, me.parentid
# FROM
#     person me
# CONNECT BY
#     parentid = prior persionid


connect_by_nocycle => { parentid => 'prior personid' }

# adds a connect by statement to the query:
# SELECT
#     me.persionid me.firstname, me.lastname, me.parentid
# FROM
#     person me
# CONNECT BY NOCYCLE
#     parentid = prior persionid

start_with

Value: \%condition

A hashref of conditions which specify the root row(s) of the hierarchy.

It uses the same syntax as "search" in DBIx::Class::ResultSet

start_with => { firstname => 'Foo', lastname => 'Bar' }

# SELECT
#     me.persionid me.firstname, me.lastname, me.parentid
# FROM
#     person me
# START WITH
#     firstname = 'foo' and lastname = 'bar'
# CONNECT BY
#     parentid = prior persionid

order_siblings_by

Value: ($order_siblings_by | \@order_siblings_by)

Which column(s) to order the siblings by.

It uses the same syntax as "order_by" in DBIx::Class::ResultSet

'order_siblings_by' => 'firstname ASC'

# SELECT
#     me.persionid me.firstname, me.lastname, me.parentid
# FROM
#     person me
# CONNECT BY
#     parentid = prior persionid
# ORDER SIBLINGS BY
#     firstname ASC

FURTHER QUESTIONS?

Check the list of additional DBIC resources.

COPYRIGHT AND LICENSE

This module is free software copyright by the DBIx::Class (DBIC) authors. You can redistribute it and/or modify it under the same terms as the DBIx::Class library.