Merged r22475 to r22477 from trunk to 5.1-stable (#39737).

git-svn-id: https://svn.redmine.org/redmine/branches/5.1-stable@22480 e93f8b46-1217-0410-a6f0-8f06a7374b81

config/database.yml.example

   password: ""
   # Use "utf8" instead of "utfmb4" for MySQL prior to 5.7.7
   encoding: utf8mb4
+  variables:
+    # Recommended `transaction_isolation` for MySQL to avoid concurrency issues is
+    # `READ-COMMITTED`.
+    # In case of MySQL lower than 8, the variable name is `tx_isolation`.
+    # See https://www.redmine.org/projects/redmine/wiki/MySQL_configuration
+    transaction_isolation: "READ-COMMITTED"
 
 development:
   adapter: mysql2
   password: ""
   # Use "utf8" instead of "utfmb4" for MySQL prior to 5.7.7
   encoding: utf8mb4
+  variables:
+    transaction_isolation: "READ-COMMITTED"
 
 # Warning: The database defined as "test" will be erased and
 # re-generated from your development database when you run "rake".
   password: ""
   # Use "utf8" instead of "utfmb4" for MySQL prior to 5.7.7
   encoding: utf8mb4
+  variables:
+    transaction_isolation: "READ-COMMITTED"
 
 # PostgreSQL configuration example
 #production:

doc/INSTALL

 * Ruby 2.7, 3.0, 3.1, 3.2
 
 * A database:
-  * MySQL (tested with MySQL 5.7)
-  * PostgreSQL (tested with PostgreSQL 9.5)
+  * MySQL (tested with MySQL 8)
+  * PostgreSQL (tested with PostgreSQL 14)
   * SQLite3 (tested with SQLite 3.11)
   * SQLServer (tested with SQLServer 2012)
 
    Go to "Administration" to load the default configuration data (roles,
    trackers, statuses, workflow) and to adjust the application settings
 
+== Database server configuration
+
+When using MySQL with Redmine 5.1.1 or later, it is necessary to change
+the transaction isolation level from the default REPEATABLE READ to
+READ_COMMITTED. To modify this setting, either change the database
+configuration file or alter the settings on your MySQL server.
+
+To set the transaction isolation level in the database configuration file,
+add transaction_isolation variable as below:
+
+  production:
+    adapter: mysql2
+    database: redmine
+    host: localhost
+    [...]
+    variables:
+      transaction_isolation: "READ-COMMITTED"
+
+More details can be found in https://www.redmine.org/projects/redmine/wiki/MySQL_configuration.
+
 == SMTP server Configuration
 
 Copy config/configuration.yml.example to config/configuration.yml and

test/functional/timelog_report_test.rb

     get :report, :params => {:project_id => 1, :criteria => ['activity']}
     assert_response :success
 
-    assert_select 'tr.last-level:first' do
+    assert_select 'tr.last-level' do
       assert_select 'td.name', :text => 'Design'
       assert_select 'td.hours:last', :text => '165:15'
     end