Workflow user and SQL Error in Ax 2012

Error description:
Stopped workflow suddenly and throwing below error

Cannot select a record in Work items (WorkflowWorkItemTable). User: abc, Check and Approve Purchase Order.
The SQL database has issued an error.

Solution:

Give Full CIL then error not resolved. 

We check batch job and showing there  batch job for workflow work item and due date getting stopped with error shown above. I changed the status of job to waiting.System Administrator->inquiries->Batch Jobs

After that workflow error resolved.