remove ref counting, will be replaced by cleanup jobs or triggers

database/migrations/2018_07_08_193500_create_rows_table.php

@@ -15,7 +15,6 @@ class CreateRowsTable extends Migration
     {
         Schema::create('rows', function (Blueprint $table) {
             $table->increments('id');
-            $table->unsignedInteger('refs'); // used for reference counting
             $table->jsonb('data');
         });
     }

database/migrations/2018_07_08_193600_create_revisions_table.php

@@ -16,7 +16,6 @@ class CreateRevisionsTable extends Migration
         Schema::create('revisions', function (Blueprint $table) {
             $table->increments('id');
             $table->timestamps();
-            $table->unsignedInteger('refs'); // used for reference counting
             $table->unsignedInteger('ancestor_id')->index()->nullable(); // parent revision
 
             // columns specification

database/migrations/2018_07_08_194000_create_proposals_table.php

@@ -27,17 +27,16 @@ class CreateProposalsTable extends Migration
 
             $table->jsonb('changes'); // the actual meat of the changeset is stored here
 
-            // block the delete - we must first decrement Row refs and then the proposals manually
             $table->foreign('revision_id')->references('id')->on('revisions')
-                ->onDelete('restrict');
+                ->onDelete('cascade'); // a proposal without the revision is useless
 
             // deleting the table must NOT delete the proposals, as they may be applicable to forks sharing the revision
             $table->foreign('table_id')->references('id')->on('tables')
                 ->onDelete('set null');
 
-            // block the delete - we must first decrement Row refs and then the proposals manually
+            // deleting author wipes their proposals
             $table->foreign('author_id')->references('id')->on('users')
-                ->onDelete('restrict');
+                ->onDelete('cascade');
         });
     }