* master: (56 commits)
File view buttons
Don't reset the session when the example failed, because we need capybara-screenshot to have access to it
Resolve "MR comment + system note highlight don't have the same width"
Add feature spec for dashboard state filter tabs
Wording of Mysql support.
a new feature checklist and more elaborate documentation requirements
Filter archived project in API v3 only if param present
Revert to using links instead of buttons in Issuable Index tabs.
Do not run the codeclimate job on docs-only changes
Only show gray footer space if environment actions exist
Migrate Gitlab::Git::Blob.find to Gitaly
Backport filtered search lazy token consistent state fix
Add a comment explaining how the branch clean up happens
Fix Github::Representation::PullRequest#source_branch_exists?
Add CHANGELOG
Fix GitHub importer performance on branch existence check
Rebuild the dynamic path before validating it
Rename stage ref migration specs to match a class name
Enable Style/DotPosition Rubocop 👮
Revert "Merge branch 'winh-merge-request-related-issues' into 'master'"
...
Conflicts:
db/post_migrate/20170526185921_migrate_build_stage_reference.rb
Starting with GitLab 9.1.0 we will no longer allow downtime migrations
unless absolutely necessary. This commit updates the various developer
guides and adds code that is necessary to make zero downtime migrations
less painful.
This was initially not implemented simply because I forgot about the
size limit of constraint names in PostgreSQL (63 bytes). Using the old
technique we can't add foreign keys for certain tables. For example,
adding a foreign key on
protected_branch_merge_access_levels.protected_branch_id would lead to
the following key name:
fk_protected_branch_merge_access_levels_protected_branches_protected_branch_id
This key is 78 bytes long, thus violating the PostgreSQL size
requirements.
The hashing strategy is copied from Rails' foreign_key_name() method,
which unfortunately is private and subject to change without notice.
This method allows one to create foreign keys without blocking access to
the source table, but only on PostgreSQL.
When creating a regular foreign key the "ALTER TABLE" statement used for
this won't return until all data has been validated. This statement in
turn will acquire a lock on the source table. As a result this lock can
be held for quite a long amount of time, depending on the number of rows
and system load.
By breaking up the foreign key creation process in two steps (creation,
and validation) we can reduce the amount of locking to a minimum.
Locking is still necessary for the "ALTER TABLE" statement that adds the
constraint, but this is a fast process and so will only block access for
a few milliseconds.
This ensures that whatever locks are acquired aren't held onto until the
end of the transaction (= after _all_ rows have been updated). Timing
wise there's also no difference between using a transaction and not
using one.
By passing a block to update_column_in_batches() one can now customize
the queries executed. This in turn can be used to only update a specific
set of rows instead of simply all the rows in the table.
These helpers can be used to perform migrations without taking down the
entire application.
For example, the method "add_column_with_default" can be used to add a
new column with a default value without locking the entire table.
Rémy Coutable
Grzegorz Bizon
Grzegorz Bizon
blackst0ne
Nick Thomas
Lin Jen-Shin
Douwe Maan
Yorick Peterse
Bob Van Landuyt
Douwe Maan
Tiago Botelho
Drew Blessing
Stan Hu
Felipe Artur