Version number for many-many-through "join" items doesn’t ever change

[kinglozzer]

Perhaps this is expected, just struck me as odd. Given the following versioned models:

• Project
• Type
• ProjectType - the “through“ object linking projects & types

I added a CheckboxSetField for linking them which works, but every record in the ProjectType_Versions table has the same Version number. For example, if I tick a “type” & publish, then untick & publish, then re-tick & publish the same “type”, there are 2 records in the versions table that are effectively identical:

[tractorcow]

I'll look into this and respond to it later.

[tractorcow]

If you aren't making changes to the relationship, and you save, and there are new rows created, it probably shouldn't create a new version just for draft.

However, if you publish a record it probably should create a new row. Except in your example above I don't see WasPublished set to 1, so I'm not sure what is going on specifically in your example.

What would concern me is that the ID column of ProjectType is incremented for each save; If you need to create a new record each save, instead of re-using existing mapping records, that may be a problem.

[tractorcow]

@kinglozzer please provide framework version, and either some example code and I'll reproduce it locally. Make sure you declare:

• any ownership
• specific relationship config
• formfields used

[kinglozzer]

Thanks @tractorcow, I’ve dumped the simplified models into a Github gist: https://gist.github.com/kinglozzer/17fd89233f5026011206de3319707966. composer show:

composer/ca-bundle                        1.1.0   Lets you find a path to t...
composer/installers                       v1.5.0  A multi-framework Compose...
embed/embed                               v3.3.1  PHP library to retrieve p...
guzzlehttp/psr7                           1.4.2   PSR-7 message implementat...
intervention/image                        2.4.1   Image handling and manipu...
league/flysystem                          1.0.43  Filesystem abstraction: M...
m1/env                                    2.1.0   Env is a lightweight libr...
marcj/topsort                             1.1.0   High-Performance TopSort/...
monolog/monolog                           1.23.0  Sends your logs to files,...
nikic/php-parser                          v3.1.5  A PHP parser written in PHP
paragonie/random_compat                   v2.0.11 PHP 5.x polyfill for rand...
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psr/http-message                          1.0.1   Common interface for HTTP...
psr/log                                   1.0.2   Common interface for logg...
psr/simple-cache                          1.0.1   Common interfaces for sim...
silverstripe/admin                        1.1.0   SilverStripe admin interface
silverstripe/asset-admin                  1.1.0   Asset management for the ...
silverstripe/assets                       1.1.0   SilverStripe Assets compo...
silverstripe/config                       1.0.4   SilverStripe configuratio...
silverstripe/framework                    4.1.0   The SilverStripe framework
silverstripe/graphql                      1.1.0   GraphQL server for Silver...
silverstripe/recipe-plugin                1.1.0   Helper plugin to install ...
silverstripe/vendor-plugin                1.3.1   Allows vendor modules to ...
silverstripe/versioned                    1.1.0   SilverStripe Versioned co...
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symbiote/silverstripe-gridfieldextensions 3.1.1   A collection of useful gr...
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symfony/filesystem                        v3.4.6  Symfony Filesystem Component
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symfony/translation                       v2.8.36 Symfony Translation Compo...
symfony/yaml                              v3.4.6  Symfony Yaml Component
webonyx/graphql-php                       v0.8.0  A PHP port of GraphQL ref...

There’s no ownership set up between projects and project types, adding that didn’t seem to make any difference

[tractorcow]

Thanks I'll check it out now. ;)

[tractorcow]

Ok, I've done my research and I can resolve this with explanation for how this works;

Because the ProjectType mapping dataobject has NO extra fields (only parent / child relations) there will never be the need to create a "new" version of an existing record.

When you unassign a many_many and re-assign it, you aren't creating a new version of the same relation, you are deleting that record, and creating a brand new record for that relation. Two record creations (different RecordID) but each is only ever created and never modified (unless it's deleted). These versions never get a chance to create Version 2, because their values never change.

If you look at your example, the records aren't identical, they have two different RecordIDs. This would be synonymous with me creating a home page, archiving it, and then manually re-creating a brand new home page with identical fields. It would have the same Version (assuming it was saved the same number of times) but it would have a different ID (RecordID in versions table).

I hope that explains things!

[kinglozzer]

I hope that explains things!

Perfectly 😁