t_node_hi_info, t_proc_info, and ACT_HI_TASKINST — along with explanations and an example showing

🔹 1. ACT_HI_TASKINST (from Activiti)

Meaning: Stores history of user tasks (e.g., approvals, actions) that were already executed in a process.

Key Fields (typical):

Field	Description
ID_	Task instance ID
PROC_INST_ID_	Process instance ID
TASK_DEF_KEY_	Task definition key from BPMN
ASSIGNEE_	User assigned
NAME_	Task name
START_TIME_	When task started
END_TIME_	When task ended
DURATION_	Time taken

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🔹 2. t_proc_info (custom / business-specific table)

Meaning: Stores business process instance info (e.g., order approval, contract signing). It links the business entity to the process engine instance (like ACT_HI_PROCINST).

Key Fields (typical):

Field	Description
id	Primary key
biz_id	Business ID (e.g., order ID)
proc_inst_id	Link to Activiti's PROC_INST_ID_
status	Current process status
start_user	Who started the process

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🔹 3. t_node_hi_info (custom / business-specific table)

Meaning: Stores node-level task history in more detail or with custom business data (e.g., opinions, comments, special fields beyond Activiti’s standard ACT_HI_TASKINST).

Key Fields (typical):

Field	Description
id	Primary key
proc_inst_id	Process instance ID
task_id	Task ID (from ACT_HI_TASKINST.ID_)
node_key	Task definition key (TASK_DEF_KEY_)
assignee	User who handled the task
comment	Approval comment
result	Pass / Reject, etc.
end_time	Task completion time

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🔄 How They Work Together (Example)

Let’s assume someone submits a Leave Application:

Step 1: Start Process

• A new row is inserted into t_proc_info:

id = 1001, biz_id = 'leave_2024_001', proc_inst_id = 'proc_abc123', status = 'running'

Step 2: Approver1 reviews task

• Activiti inserts a row into ACT_HI_TASKINST:

ID_ = 'task_xyz111', PROC_INST_ID_ = 'proc_abc123', ASSIGNEE_ = 'manager1', NAME_ = 'Manager Approval'

• Your system inserts a row into t_node_hi_info:

task_id = 'task_xyz111', proc_inst_id = 'proc_abc123', assignee = 'manager1', comment = 'Looks good', result = 'approved'

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🧩 Visualization

[ t_proc_info ] biz_id = leave_2024_001 proc_inst_id = proc_abc123 │

▼

[ ACT_HI_TASKINST ] ID_ = task_xyz111 PROC_INST_ID_ = proc_abc123 ASSIGNEE_ = manager1 │

▼ [ t_node_hi_info ] task_id = task_xyz111 comment = 'Looks good' result = 'approved'

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✅ Use Cases

Table	Purpose
ACT_HI_TASKINST	Technical task history (standard BPM data)
t_proc_info	Business-level tracking of process instances
t_node_hi_info	Detailed/custom task node information