Strange Error on processwire page tree listing SQLSTATE[HY000]: General error: could not call class constructor

[Hari KT]

Hi,

From the processwire page tree listing, I am getting a strange error 

SQLSTATE[HY000]: General error: could not call class constructor

I am looking at http://blog.boringguys.com/2010/11/sqlstatehy000-general-error-could-not.html  when I noticed the same.

I have added a few fields and upgraded to latest version of PW in dev branch.

Any help to fix the page tree is appreciated.

Thank you

[Hari KT]

Was going through the ajax request. Below is the error I have got 

 TemplateFile: SQLSTATE[HY000]: General error: could not call class constructor

 #0 /var/www/ProcessWire/wire/core/Pages.php(0): PDOStatement->fetchObject()
 #1 /var/www/ProcessWire/wire/core/Pages.php(229): Pages->getById(Array, Array)
 #2 [internal function]: Pages->___find('parent_id=1, st...', Array)
 #3 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #4 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('find', Array)
 #5 /var/www/ProcessWire/wire/core/PageTraversal.php(78): Wire->__call('find', Array)
 #6 /var/www/ProcessWire/wire/core/PageTraversal.php(78): Pages->find('parent_id=1, st...', Array)
 #7 /var/www/ProcessWire/wire/core/Page.php(1033): PageTraversal->children(Object(Page), 'start=0, limit=...', Array)
 #8 /var/www/ProcessWire/wire/modules/Process/ProcessPageList/ProcessPageList.module(178): Page->children('start=0, limit=...')
 #9 [internal function]: ProcessPageList->___find('start=0, limit=...', Object(Page))
 #10 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #11 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('find', Array)
 #12 /var/www/ProcessWire/wire/modules/Process/ProcessPageList/ProcessPageList.module(165): Wire->__call('find', Array)
 #13 /var/www/ProcessWire/wire/modules/Process/ProcessPageList/ProcessPageList.module(165): ProcessPageList->find('start=0, limit=...', Object(Page))
 #14 /var/www/ProcessWire/wire/modules/Process/ProcessPageList/ProcessPageList.module(109): ProcessPageList->render()
 #15 [internal function]: ProcessPageList->___execute()
 #16 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #17 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('execute', Array)
 #18 /var/www/ProcessWire/wire/core/ProcessController.php(213): Wire->__call('execute', Array)
 #19 /var/www/ProcessWire/wire/core/ProcessController.php(213): ProcessPageList->execute()
 #20 [internal function]: ProcessController->___execute()
 #21 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #22 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('execute', Array)
 #23 /var/www/ProcessWire/wire/core/admin.php(85): Wire->__call('execute', Array)
 #24 /var/www/ProcessWire/wire/core/admin.php(85): ProcessController->execute()
 #25 /var/www/ProcessWire/site/modules/AdminThemeThinktag/controller.php(13): require('/var/www/Proces...')
 #26 /var/www/ProcessWire/site/templates/admin.php(13): require('/var/www/Proces...')
 #27 /var/www/ProcessWire/wire/core/TemplateFile.php(169): require('/var/www/Proces...')
 #28 [internal function]: TemplateFile->___render()
 #29 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #30 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('render', Array)
 #31 /var/www/ProcessWire/wire/modules/PageRender.module(356): Wire->__call('render', Array)
 #32 /var/www/ProcessWire/wire/modules/PageRender.module(356): TemplateFile->render()
 #33 [internal function]: PageRender->___renderPage(Object(HookEvent))
 #34 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #35 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('renderPage', Array)
 #36 /var/www/ProcessWire/wire/core/Wire.php(387): Wire->__call('renderPage', Array)
 #37 /var/www/ProcessWire/wire/core/Wire.php(387): PageRender->renderPage(Object(HookEvent))
 #38 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('render', Array)
 #39 /var/www/ProcessWire/wire/modules/Process/ProcessPageView.module(172): Wire->__call('render', Array)
 #40 /var/www/ProcessWire/wire/modules/Process/ProcessPageView.module(172): Page->render()
 #41 [internal function]: ProcessPageView->___execute()
 #42 /var/www/ProcessWire/wire/core/Wire.php(365): call_user_func_array(Array, Array)
 #43 /var/www/ProcessWire/wire/core/Wire.php(320): Wire->runHooks('execute', Array)
 #44 /var/www/ProcessWire/index.php(195): Wire->__call('execute', Array)
 #45 /var/www/ProcessWire/index.php(195): ProcessPageView->execute()
 #46 {main}

[Hari KT]

Reverting back to the old version fixed it. I was trying to update with the latest dev branch.