Re: Class DBI many to many

One important remark in the documentation:

When setting up the relationship the foreign class's has_a() declarations are examined to discover which of its columns reference our class. (Note that because this happens at compile time, if the foreign class is defined in the same file, the class with the has_a() must be defined earlier than the class with the has_many(). If the classes are in different files, Class::DBI should usually be able to do the right things, as long as all classes inherit Class::DBI before 'use'ing any other classes.)

So this should work by reordering the declarations:

package MyDictionary::En_To_Sk

MyDictionary::En_To_Sk->columns(Primary   => qw/id/);
MyDictionary::En_To_Sk->columns(Essential => qw/eng_id sk_id/);

# Declare the relationships
MyDictionary::En_To_Sk->has_a('eng_id' => "MyDictionary::Engword");
MyDictionary::En_To_Sk->has_a('sk_id' => "MyDictionary::Skword");


package MyDictionary::Engword

MyDictionary::Engword->columns(Primary   => qw/id/);
MyDictionary::Engword->has_many("translations", 'MyDictionary::En_To_S
+k', 'eng_id');


package MyDictionary::Skword

MyDictionary::Skword->columns(Primary   => qw/id/);
MyDictionary::Skword->has_many("translations", 'MyDictionary::En_To_Sk
+', 'sk_id');
[download]

I suppose you have defined the other columns. The construction "['MyDictionary::En_To_Sk' => 'engword']" in the 'has_many' function in the class 'MyDictionary::En_To_Sk' is only necessary when the values in 'eng_id' and 'sk_id' are not the primary keys used in the classes 'package MyDictionary::Engword' and 'package MyDictionary::Skword'.

Hopes this helps.

Martell

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Re^2: Class DBI many to many by zooey (Initiate) on Jun 19, 2011 at 22:15 UTC
Hi thanks for post i made it like you advised but it didn't help here is the code: ###################################################################### +########## # Package MyDictionary::DBI # # Represents object oriented form of my Database package MyDictionary::DBI; use base "Class::DBI::SQLite"; MyDictionary::DBI->set_db('Main', "dbi:SQLite:dbname=Dictionary.db"); ###################################################################### +########## # Package MyDictionary::En_To_Sk # # Represents en_to_sk table package MyDictionary::En_To_Sk; use base "MyDictionary::DBI"; MyDictionary::En_To_Sk->set_up_table('en_to_sk'); MyDictionary::En_To_Sk->columns(All => (eng_id sk_id)); MyDictionary::En_To_Sk->has_a('eng_id' => "MyDictionary::Engword"); MyDictionary::En_To_Sk->has_a('sk_id' => "MyDictionary::Skword"); # Package MyDictionary::Engword # # Represent englishword table package MyDictionary::Engword; use base "MyDictionary::DBI"; MyDictionary::Engword->set_up_table("englishword"); MyDictionary::Engword->columns(Primary => qw/eng_id/); MyDictionary::Engword->columns(All => (eng_id engword)); MyDictionary::Engword->has_many("translations", 'MyDictionary::En_To_S +k', 'eng_id'); #MyDictionary::Engword->has_many('translations',['MyDictionary::En_To_ +Sk' => 'skword'], 'engword'); ###################################################################### +########## # Package MyDictionary::Skword # # Represent skwordmeaning table package MyDictionary::Skword; use base "MyDictionary::DBI"; MyDictionary::Skword->set_up_table("skwordmeaning"); MyDictionary::Skword->columns(Primary => qw/sk_id/); MyDictionary::Skword->columns(All => (sk_id skword)); #MyDictionary::Skword->has_many('translations',['MyDictionary::En_To_S +k' => 'engword'], 'skword'); MyDictionary::Skword->has_many("translations", 'MyDictionary::En_To_Sk +', 'sk_id'); [download] Finally i've done it through DBIx it is better documented with more users. Thanks	[reply] [d/l]

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Re^2: Class DBI many to many
by zooey (Initiate) on Jun 19, 2011 at 22:15 UTC

Hi thanks for post i made it like you advised but it didn't help here is the code:

######################################################################
+##########

# Package MyDictionary::DBI
# 
# Represents object oriented form of my Database

package MyDictionary::DBI;
use base "Class::DBI::SQLite";
MyDictionary::DBI->set_db('Main', "dbi:SQLite:dbname=Dictionary.db");

######################################################################
+##########

# Package MyDictionary::En_To_Sk
#
# Represents en_to_sk table

package MyDictionary::En_To_Sk;
use base "MyDictionary::DBI";

MyDictionary::En_To_Sk->set_up_table('en_to_sk');
MyDictionary::En_To_Sk->columns(All => (eng_id sk_id));
MyDictionary::En_To_Sk->has_a('eng_id' => "MyDictionary::Engword");
MyDictionary::En_To_Sk->has_a('sk_id' => "MyDictionary::Skword");

# Package MyDictionary::Engword
# 
# Represent englishword table

package MyDictionary::Engword;
use base "MyDictionary::DBI";

MyDictionary::Engword->set_up_table("englishword");
MyDictionary::Engword->columns(Primary   => qw/eng_id/);
MyDictionary::Engword->columns(All => (eng_id engword));
MyDictionary::Engword->has_many("translations", 'MyDictionary::En_To_S
+k', 'eng_id');

#MyDictionary::Engword->has_many('translations',['MyDictionary::En_To_
+Sk' => 'skword'], 'engword');


######################################################################
+##########

# Package MyDictionary::Skword
# 
# Represent skwordmeaning table

package MyDictionary::Skword;
use base "MyDictionary::DBI";

MyDictionary::Skword->set_up_table("skwordmeaning");
MyDictionary::Skword->columns(Primary   => qw/sk_id/);
MyDictionary::Skword->columns(All => (sk_id skword));

#MyDictionary::Skword->has_many('translations',['MyDictionary::En_To_S
+k' => 'engword'], 'skword');

MyDictionary::Skword->has_many("translations", 'MyDictionary::En_To_Sk
+', 'sk_id');
[download]

[reply]
[d/l]