Tried to upgrade from 5.6.0.1 to 5.6.2.1 and it fails with the following:
An Unexpected Error occurred while upgrading:
#0 /home/concrete/libraries/3rdparty/adodb/adodb.inc.php(1074): adodb_throw('mysqlt', 'EXECUTE', 1064, 'You have an err...', 'SELECT TABLE_NA...', false, Object(ADODB_mysqlt))
#1 /home/concrete/libraries/3rdparty/adodb/adodb.inc.php(1049): ADOConnection->_Execute('SELECT TABLE_NA...', false)
#2 /home/concrete/libraries/3rdparty/adodb/adodb.inc.php(2334): ADOConnection->Execute('SELECT TABLE_NA...')
#3 /home/concrete/libraries/3rdparty/adodb/drivers/adodb-mysql.inc.php(150): ADOConnection->MetaTables(false, false)
#4 /home/concrete/core/libraries/cache.php(166): ADODB_mysql->MetaTables()
#5 /home/concrete/core/controllers/single_pages/upgrade.php(238): Concrete5_Library_Cache->flush()
#6 /home/concrete/core/controllers/single_pages/upgrade.php(44): Concrete5_Controller_Upgrade->do_upgrade()
#7 /home/concrete/core/libraries/controller.php(264): Concrete5_Controller_Upgrade->view('tools', 'required', 'upgrade')
#8 /home/concrete/core/libraries/controller.php(234): Concrete5_Library_Controller->runTask(Array, Array)
#9 /home/concrete/core/libraries/view.php(783): Concrete5_Library_Controller->setupAndRun('view', Array)
#10 /home/concrete/tools/upgrade.php(6): Concrete5_Library_View->render()
#11 /home/concrete/startup/tools_upgrade_check.php(9): include('/hsphere/local/...')
#12 /home/concrete/dispatcher.php(105): require('/hsphere/local/...')
#13 /home/index.php(2): require('/hsphere/local/...')
#14 {main}

I then tried to upfgrade from 5.6.0.1. to 5.6.1.2 and it worked.
I then tried to upgrade to 5.6.2 and it fails in the same way.
I was unable to download and install, so I reverted to the upgrade where you replace the concrete directly with the new concrete directory and run the upgrade using
http://www.domain.com/index.php/tools/required/upgrade...

Looks like a database issue, but any ideas how to resolve>

Thanks