Merge branch 'master' into 33361-make-scroll-faster33361-make-scroll-faster

* master: (92 commits)
  Responsive table fixes
  remove the rouge copypasta and add notes to refactor
  nil-check Repository::is_ancestor?
  update rouge to 2.1.0
  Added more negative checks for public project
  Fix End Syntax Error
  Enhancing Spec's with negative cases
  Improve form spec
  Update CHANGELOG.md for 9.0.10
  Update CHANGELOG.md for 9.2.5
  Fixed spec test syntax errors
  Update CHANGELOG.md for 9.1.7
  Translate project & repository pages
  Converting Tests to Spec Tests
  Added more actions and report as abuse to all notes
  Add sticky confidential issue bar
  Fix for Login Test Problem
  Document not using STI
  Added Cop to blacklist polymorphic associations
  Document not using polymorphic associations
  ...

1 files changed, 18 insertions, 0 deletions

diff --git a/doc/development/single_table_inheritance.md b/doc/development/single_table_inheritance.md
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+# Single Table Inheritance
+
+**Summary:** don't use Single Table Inheritance (STI), use separate tables
+instead.
+
+Rails makes it possible to have multiple models stored in the same table and map
+these rows to the correct models using a `type` column. This can be used to for
+example store two different types of SSH keys in the same table.
+
+While tempting to use one should avoid this at all costs for the same reasons as
+outlined in the document ["Polymorphic Associations"](polymorphic_associations.md).
+
+## Solution
+
+The solution is very simple: just use a separate table for every type you'd
+otherwise store in the same table. For example, instead of having a `keys` table
+with `type` set to either `Key` or `DeployKey` you'd have two separate tables:
+`keys` and `deploy_keys`.