Please see this: https://confluence.atlassian.com/confkb/confluence-fails-to-start-and-throws-mysql-session-isolation-level-repeatable-read-is-no-longer-supported-error-241568536.html

And do not add a ?sessionVariables=tx_isolation='READ-COMMITTED' to server.xml configs or Confluence do not startup.

Unfortunatelly PostgreSQL is not supported on Timesheet for Confluence.

You can try to make this configuration with your own risk. Please see at: https://tomcat.apache.org/tomcat-7.0-doc/jndi-datasource-examples-howto.html

<Resource
name="jdbc/agileapplicationstack"
auth="Container"
type="javax.sql.DataSource"
driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://localhost:5432/timesheet?autoReconnect=true"
username="timesheet"
password="password"
maxActive="20"
maxIdle="10"
maxWait="-1"
/>
Instead configuration below.

Prepare the external MySQL database to your Confluence before installing a plugin

Do I need to install MySQL connector?

Yes. MySQL J-connector is not bundled in Confluence so you need to install it to ./lib-folder.

Edit server.xml file

You need to add MaxTotal and it's value to Resource xml-tag:

https://confluence.atlassian.com/confkb/startup-check-http-maxthreads-configuration-939930122.html

In ./conf/server.xml file:

<Host name="localhost" debug="0" appBase="webapps" unpackWARs="true" autoDeploy="false">
 
                <Context path="" docBase="../confluence" debug="0" reloadable="false">
                    <!-- Logger is deprecated in Tomcat 5.5. Logging configuration for Confluence is specified in confluence/WEB-INF/classes/log4j.properties -->
                    <Manager pathname="" /> <-- Find this...
... Add this after
<Resource
name="jdbc/agileapplicationstack"
auth="Container"
type="javax.sql.DataSource"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost/timesheet?autoReconnect=true"
username="timesheet"
password="password"
maxActive="25"
maxIdle="5"
maxWait="10000"
/>

Always you upgrade the Confluence you need make this configuration again manually. So backup your ./conf/server.xml first you proceed the upgrade. Do not replace new file with old file. Please just edit new one.

Create database (on command line or with phpMyAdmin)

Create a database timesheet.

Import SQL file (on command line or with phpMyAdmin)

Run timesheet_conf.sql file to your database. And since Timesheet for Confluence version 1.8 run also timesheet_for_approval.sql file to your database.

Restart Confluence now.

Macros

Write this to a wiki page in a space:

{grid-timesheet}

To see all users in the timesheet:

{grid-admin-timesheet}

To make user timesheet:

{grid-user-timesheet:user_id=admin|timesheet_id=timesheet_1|month=5|year=2017}

Since version 1.9 user timesheets can be approved by administrators or users who can edit a Confluence page:

{grid-user-timesheet:user_id=admin|timesheet_id=timesheet_1|month=5|year=2017|approved=true}
{grid-user-timesheet:user_id=admin|timesheet_id=timesheet_1|month=5|year=2017|approved=false}


How to use these macros on Confluence Pages?

Timesheet for Confluence Step by Step

Timesheet for Confluence - How to work with User Timesheets