README.rdoc in composite_primary_keys-12.0.9 vs README.rdoc in composite_primary_keys-12.0.10

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@@ -1,180 +1,180 @@ -= Composite Primary Keys for ActiveRecords - -== Summary - -ActiveRecords infamously doesn't support composite primary keys. -This gem, composite_primary_keys, or CPK for short, extends ActiveRecord -to support composite keys. - -== Installation - - gem install composite_primary_keys - -If you are using Rails add the following to your Gemfile: - - gem 'composite_primary_keys', '=x.x.x' (see next section about what version to use) - -== Versions - -Every major version of ActiveRecord has included numerous internal changes. As a result, -CPK has to be rewritten for each version of ActiveRecord. To help keep -things straight, here is the mapping: - - Version 12.x is designed to work with ActiveRecord 6.0.x - Version 11.x is designed to work with ActiveRecord 5.2.x - Version 10.x is designed to work with ActiveRecord 5.1.x - Version 9.x is designed to work with ActiveRecord 5.0.x - Version 8.x is designed to work with ActiveRecord 4.2.x - Version 7.x is designed to work with ActiveRecord 4.1.x - Version 6.x is designed to work with ActiveRecord 4.0.x - Version 5.x is designed to work with ActiveRecord 3.2.x - Version 4.x is designed to work with ActiveRecord 3.1.x - -Run the following command to list available versions: - - gem list composite_primary_keys -ra - -== The basics - -A model with composite primary keys is defined like this: - - class Membership < ActiveRecord::Base - self.primary_keys = :user_id, :group_id - belongs_to :user - belongs_to :group - has_many :statuses, :class_name => 'MembershipStatus', :foreign_key => [:user_id, :group_id] - end - -Note the addition of the line: - - self.primary_keys = :user_id, :group_id - - -A model associated with a composite key model is defined like this: - - class MembershipStatus < ActiveRecord::Base - belongs_to :membership, :foreign_key => [:user_id, :group_id] - end - -That is, associations can include composite keys too. All Rails association types are supported. Nice. - -== Usage - -Once you’ve created your models to specify composite primary keys (such as the Membership class) -and associations (such as MembershipStatus#membership), you can use them like any normal model -with associations. - -But first, lets check out our primary keys. - - MembershipStatus.primary_key # => "id" # normal single key - Membership.primary_key # => [:user_id, :group_id] # composite keys - Membership.primary_key.to_s # => "user_id,group_id" - -Now we want to be able to find instances using the same syntax we always use for ActiveRecords… - - MembershipStatus.find(1) # single id returns single instance - => <MembershipStatus:0x392a8c8 @attributes={"id"=>"1", "status"=>"Active"}> - - Membership.find([1,1]) # composite ids returns single instance - => <Membership:0x39218b0 @attributes={"user_id"=>"1", "group_id"=>"1"}> - -Notice the use of an array to specify the composite key values. - -NOTE - API CHANGE. CPK Version 6.x and earlier used to allow composite keys to be listed out -like this: - - Membership.find(1,1) - -This usage is no longer supported. - -== Databases - -CPK supports the following databases: - - * PostgreSQL - * MySQL - * MariaDB - * Oracle - * DB2 - * SQLite - * SQLServer - -== Tests - -To run tests you first need to install the appropriate gems for the database you want to test. Database gems are -divided into the following bundler groups: - - * mysql - * oracle - * postgresql - * sqlite - * sqlserver - -Since it is likely you do not have all the above databases installed on your computer, you want to install just the -gems for your database. For example, to test postgresql you would install the appropriate gems like this: - - bundler config set --local without "mysql oracle sqlite sqlserver" - bundler install - -Once you have installed the appropriate gems, the next step is to create the test database. There is a rake -command for each database. Using our example: - - rake postgresql:build_database - -You can also rebuild the database if it already exists using this command: - - rake postgresql:rebuild_database - -To get a list of commands for your database use: - - Rake -T - -Finally, to run tests: - - rake postgresql:test - -Travis build status: {<img src="https://travis-ci.com/composite-primary-keys/composite_primary_keys.svg" alt="Build Status" />}[https://travis-ci.com/composite-primary-keys/composite_primary_keys] - -=== DB2 - -DB2 is no longer supported due to difficulties in getting the ibm_db2 gem to build. Thus tests -have not been run against db2. - -=== MariaDb (mysql) - -MariaDb is fully supported with all tests passing. - -=== Oracle - -Oracle is fully supported with all tests passing. - -=== Postgresql - -Postgresql is fully supported with all tests passing. - -=== Sqlite 3 - -The sqlite database is created at the path composite_primary_keys/db. Note you must *first* create the database using the -built-in rake task before running tests: - - rake sqlite:build_database - -For sqlite3 to work correctly, you must manually require 'composite_primary_keys/connection_adapters/sqlite3_adapter' after -loading the CPK gem. - -=== SqlServer - -SqlServer is partially supported. There are a number of failing tests - patches welcomed. - -== Questions, Discussion and Contributions - -For help please visit https://github.com/composite-primary-keys/composite_primary_keys. - -== Author - -First version was written by Dr Nic Williams. - -Maintained by Charlie Savage - -Contributions by many! - += Composite Primary Keys for ActiveRecords + +== Summary + +ActiveRecords infamously doesn't support composite primary keys. +This gem, composite_primary_keys, or CPK for short, extends ActiveRecord +to support composite keys. + +== Installation + + gem install composite_primary_keys + +If you are using Rails add the following to your Gemfile: + + gem 'composite_primary_keys', '=x.x.x' (see next section about what version to use) + +== Versions + +Every major version of ActiveRecord has included numerous internal changes. As a result, +CPK has to be rewritten for each version of ActiveRecord. To help keep +things straight, here is the mapping: + + Version 12.x is designed to work with ActiveRecord 6.0.x + Version 11.x is designed to work with ActiveRecord 5.2.x + Version 10.x is designed to work with ActiveRecord 5.1.x + Version 9.x is designed to work with ActiveRecord 5.0.x + Version 8.x is designed to work with ActiveRecord 4.2.x + Version 7.x is designed to work with ActiveRecord 4.1.x + Version 6.x is designed to work with ActiveRecord 4.0.x + Version 5.x is designed to work with ActiveRecord 3.2.x + Version 4.x is designed to work with ActiveRecord 3.1.x + +Run the following command to list available versions: + + gem list composite_primary_keys -ra + +== The basics + +A model with composite primary keys is defined like this: + + class Membership < ActiveRecord::Base + self.primary_keys = :user_id, :group_id + belongs_to :user + belongs_to :group + has_many :statuses, :class_name => 'MembershipStatus', :foreign_key => [:user_id, :group_id] + end + +Note the addition of the line: + + self.primary_keys = :user_id, :group_id + + +A model associated with a composite key model is defined like this: + + class MembershipStatus < ActiveRecord::Base + belongs_to :membership, :foreign_key => [:user_id, :group_id] + end + +That is, associations can include composite keys too. All Rails association types are supported. Nice. + +== Usage + +Once you’ve created your models to specify composite primary keys (such as the Membership class) +and associations (such as MembershipStatus#membership), you can use them like any normal model +with associations. + +But first, lets check out our primary keys. + + MembershipStatus.primary_key # => "id" # normal single key + Membership.primary_key # => [:user_id, :group_id] # composite keys + Membership.primary_key.to_s # => "user_id,group_id" + +Now we want to be able to find instances using the same syntax we always use for ActiveRecords… + + MembershipStatus.find(1) # single id returns single instance + => <MembershipStatus:0x392a8c8 @attributes={"id"=>"1", "status"=>"Active"}> + + Membership.find([1,1]) # composite ids returns single instance + => <Membership:0x39218b0 @attributes={"user_id"=>"1", "group_id"=>"1"}> + +Notice the use of an array to specify the composite key values. + +NOTE - API CHANGE. CPK Version 6.x and earlier used to allow composite keys to be listed out +like this: + + Membership.find(1,1) + +This usage is no longer supported. + +== Databases + +CPK supports the following databases: + + * PostgreSQL + * MySQL + * MariaDB + * Oracle + * DB2 + * SQLite + * SQLServer + +== Tests + +To run tests you first need to install the appropriate gems for the database you want to test. Database gems are +divided into the following bundler groups: + + * mysql + * oracle + * postgresql + * sqlite + * sqlserver + +Since it is likely you do not have all the above databases installed on your computer, you want to install just the +gems for your database. For example, to test postgresql you would install the appropriate gems like this: + + bundler config set --local without "mysql oracle sqlite sqlserver" + bundler install + +Once you have installed the appropriate gems, the next step is to create the test database. There is a rake +command for each database. Using our example: + + rake postgresql:build_database + +You can also rebuild the database if it already exists using this command: + + rake postgresql:rebuild_database + +To get a list of commands for your database use: + + Rake -T + +Finally, to run tests: + + rake postgresql:test + +Travis build status: {<img src="https://travis-ci.com/composite-primary-keys/composite_primary_keys.svg" alt="Build Status" />}[https://travis-ci.com/composite-primary-keys/composite_primary_keys] + +=== DB2 + +DB2 is no longer supported due to difficulties in getting the ibm_db2 gem to build. Thus tests +have not been run against db2. + +=== MariaDb (mysql) + +MariaDb is fully supported with all tests passing. + +=== Oracle + +Oracle is fully supported with all tests passing. + +=== Postgresql + +Postgresql is fully supported with all tests passing. + +=== Sqlite 3 + +The sqlite database is created at the path composite_primary_keys/db. Note you must *first* create the database using the +built-in rake task before running tests: + + rake sqlite:build_database + +For sqlite3 to work correctly, you must manually require 'composite_primary_keys/connection_adapters/sqlite3_adapter' after +loading the CPK gem. + +=== SqlServer + +SqlServer is partially supported. There are a number of failing tests - patches welcomed. + +== Questions, Discussion and Contributions + +For help please visit https://github.com/composite-primary-keys/composite_primary_keys. + +== Author + +First version was written by Dr Nic Williams. + +Maintained by Charlie Savage + +Contributions by many! +