1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
# See http://doc.gitlab.com/ce/development/migration_style_guide.html
# for more information on how to write migrations for GitLab.
# rubocop:disable RemoveIndex
class RemoveRedundantIndexes < ActiveRecord::Migration
include Gitlab::Database::MigrationHelpers
DOWNTIME = false
disable_ddl_transaction!
def up
indexes = [
[:ci_taggings, 'ci_taggings_idx'],
[:audit_events, 'index_audit_events_on_author_id'],
[:audit_events, 'index_audit_events_on_type'],
[:ci_builds, 'index_ci_builds_on_erased_by_id'],
[:ci_builds, 'index_ci_builds_on_project_id_and_commit_id'],
[:ci_builds, 'index_ci_builds_on_type'],
[:ci_commits, 'index_ci_commits_on_project_id'],
[:ci_commits, 'index_ci_commits_on_project_id_and_committed_at'],
[:ci_commits, 'index_ci_commits_on_project_id_and_committed_at_and_id'],
[:ci_commits, 'index_ci_commits_on_project_id_and_sha'],
[:ci_commits, 'index_ci_commits_on_sha'],
[:ci_events, 'index_ci_events_on_created_at'],
[:ci_events, 'index_ci_events_on_is_admin'],
[:ci_events, 'index_ci_events_on_project_id'],
[:ci_jobs, 'index_ci_jobs_on_deleted_at'],
[:ci_jobs, 'index_ci_jobs_on_project_id'],
[:ci_projects, 'index_ci_projects_on_gitlab_id'],
[:ci_projects, 'index_ci_projects_on_shared_runners_enabled'],
[:ci_services, 'index_ci_services_on_project_id'],
[:ci_sessions, 'index_ci_sessions_on_session_id'],
[:ci_sessions, 'index_ci_sessions_on_updated_at'],
[:ci_tags, 'index_ci_tags_on_name'],
[:ci_triggers, 'index_ci_triggers_on_deleted_at'],
[:identities, 'index_identities_on_created_at_and_id'],
[:issues, 'index_issues_on_title'],
[:keys, 'index_keys_on_created_at_and_id'],
[:members, 'index_members_on_created_at_and_id'],
[:members, 'index_members_on_type'],
[:milestones, 'index_milestones_on_created_at_and_id'],
[:namespaces, 'index_namespaces_on_visibility_level'],
[:projects, 'index_projects_on_builds_enabled_and_shared_runners_enabled'],
[:services, 'index_services_on_category'],
[:services, 'index_services_on_created_at_and_id'],
[:services, 'index_services_on_default'],
[:snippets, 'index_snippets_on_created_at'],
[:snippets, 'index_snippets_on_created_at_and_id'],
[:todos, 'index_todos_on_state'],
[:web_hooks, 'index_web_hooks_on_created_at_and_id'],
# These indexes _may_ be used but they can be replaced by other existing
# indexes.
# There's already a composite index on (project_id, iid) which means that
# a separate index for _just_ project_id is not needed.
[:issues, 'index_issues_on_project_id'],
# These are all composite indexes for the columns (created_at, id). In all
# these cases there's already a standalone index for "created_at" which
# can be used instead.
#
# Because the "id" column of these composite indexes is never needed (due
# to "id" already being indexed as its a primary key) these composite
# indexes are useless.
[:issues, 'index_issues_on_created_at_and_id'],
[:merge_requests, 'index_merge_requests_on_created_at_and_id'],
[:namespaces, 'index_namespaces_on_created_at_and_id'],
[:notes, 'index_notes_on_created_at_and_id'],
[:projects, 'index_projects_on_created_at_and_id'],
[:users, 'index_users_on_created_at_and_id'],
]
transaction do
indexes.each do |(table, index)|
remove_index(table, name: index) if index_exists_by_name?(table, index)
end
end
add_concurrent_index(:users, :created_at)
add_concurrent_index(:projects, :created_at)
add_concurrent_index(:namespaces, :created_at)
end
def down
# We're only restoring the composite indexes that could be replaced with
# individual ones, just in case somebody would ever want to revert.
transaction do
remove_index(:users, :created_at)
remove_index(:projects, :created_at)
remove_index(:namespaces, :created_at)
end
[:issues, :merge_requests, :namespaces, :notes, :projects, :users].each do |table|
add_concurrent_index(table, [:created_at, :id],
name: "index_#{table}_on_created_at_and_id")
end
end
# Rails' index_exists? doesn't work when you only give it a table and index
# name. As such we have to use some extra code to check if an index exists for
# a given name.
def index_exists_by_name?(table, index)
indexes_for_table[table].include?(index)
end
def indexes_for_table
@indexes_for_table ||= Hash.new do |hash, table_name|
hash[table_name] = indexes(table_name).map(&:name)
end
end
end
|
