Workflow related tables and basic on how fix HR related workflow issue

WF_ACTIVITIES table stores the definition of an activity. Activities can be processes, notifications, functions or folders. A process activity is a modelled workflow process, which can be included as an activity in other processes to represent a sub process. A notification activity sends a message to a performer. A functions activity performs an automated function that is written as a PL/SQL stored procedure. A folder activity is not part of a process, it provides a means of grouping activities.

WF_ITEMS is the runtime table for workflow processes. Each row defines one work item within the system.

The WF_ITEM_ATTRIBUTES table stores definitions of attributes associated with a process. Each row includes the sequence in which the attribute is used as well as the format of the attribute data.

WF_NOTIFICATIONS holds the runtime information about a specific instance of a sent message. A new row is created in the table each time a message is sent.

hr_api_transactions is a place to hold the HR workflows in process

To remove a workflow do the following
execute hr_transaction_api.rollback_transaction( p_transaction_id => 3350154, p_validate => false);
commit;
execute wf_engine.abortprocess  (itemtype => 'HRSSA',  itemkey => '235642');
commit;
execute wf_purge.items (itemtype => 'HRSSA',itemkey => '235642' );
commit;

Oracle Workflow tables

WF_ACTIVITIES table stores the definition of an activity. Activities can
be processes, notifications, functions or folders. A process activity is a
modelled workflow process, which can be included as an activity in
other processes to represent a sub–process. A notification activity sends
a message to a performer. A functions activity performs an automated
function that is written as a PL/SQL stored procedure. A folder activity
is not part of a process, it provides a means of grouping activities.

WF_ITEMS is the runtime table for workflow processes. Each row
defines one work item within the system.

WF_ITEM_ATTRIBUTES table stores definitions of attributes
associated with a process. Each row includes the sequence in which the
attribute is used as well as the format of the attribute data.

WF_NOTIFICATIONS holds the runtime information about a specific
instance of a sent message. A new row is created in the table each time a
message is sent.

220: Unable to set NLS_LANGUAGE Error When Connecting to the Database From Oracle Workflow Builder

Set NLS_LANG as an operating system environment variable:

1. Select Start - Control Panel - System

2. Select Environment 

3. Set NLS_LANG parameter to AMERICAN_AMERICA.UTF8