DataBuddy workflows support parameter configuration at two levels: workflow parameters and task parameters. Workflow parameters define globally shared Key-Value pairs that are automatically inherited by all tasks within the workflow. Task parameters define task-specific Key-Value pairs that apply only to the current task.
Overview
Layer | Definition Location | Scope | Priority |
Workflow parameter | Workflow configuration drawer | Automatically inherited by all tasks in the workflow | Low |
Task parameter. | Task configuration panel | Current task only | High |
Prerequisites
You are already the workflow owner or have Manage permission.
Configuring Workflow Parameters
Entries
On the Data Development page, open the target workflow, and then choose Parameters > Parameter Management in the configuration drawer on the right.
Step 1: Entering Parameter Configuration
1. Open the workflow details page.
2. In the drawer on the right, click Parameters > Parameter Management.
Step 2: UI Mode - Adding Parameters
1. By default, the pop-up window is in UI mode.
2. Click + to add a row of parameters:
Parameter Name: Required. It supports all languages, uppercase and lowercase letters, digits, _, and -, with a maximum length of 128 characters.
Parameter Value: Required. It must be a string with a maximum length of 2048 characters.
3. Click Confirm to save.
Step 3: JSON Mode - Batch Editing
1. Click JSON Mode in the upper-right corner of the pop-up window to switch to the JSON editor.
2. Enter an object that conforms to the JSON specification, for example:
{
"dp_data_dt": "{{workflow.start_time.iso_date}}",
"env": "production",
"batch_size": "1000"
}
3. Syntax is validated in real time during editing. If an error occurs, an error message is displayed below, and the Confirm button is grayed out.
4. Click Confirm to save.
Note:
JSON mode does not support nested structures. It supports only first-level key-value pairs, and all values must be strings.
Step 4: Deleting Parameters
UI mode: Click the delete icon at the end of the parameter row.
JSON mode: Directly edit the JSON to delete the corresponding key-value pair.
Step 5: Saving and Viewing
After saving, the parameter list is displayed in the Parameters section of the workflow configuration drawer. Each row displays one parameter, with a maximum of 20 parameters displayed. Scrolling is available for additional parameters.
Configuring Task Parameters
Entries
On the Data Development page, open the target workflow > choose Task Orchestration > click the target task node in the canvas > go to the Parameter Configuration section in the task configuration below.
Step 1: Viewing Inherited Workflow Parameters
The parameters inherited from the workflow are displayed at the top of the Parameters section in the task panel. Each row contains:
Column | Description |
Parameter Name | Workflow parameter name, grayed out and not editable. |
Parameter Value | Workflow parameter value, not editable. |
Step 2: Adding Task Parameters
1. Click + Add to add a row of task parameters.
2. Enter:
Parameter Name: It supports all languages, uppercase and lowercase letters, digits, _, and -, with a maximum length of 128 characters. It cannot have the same name as an existing inherited workflow parameter or another task parameter.
Parameter Value: A string with a maximum length of 2048 characters.
3. Click Save Task.
Step 3: When Parameters Have the Same Name as Workflow Parameters
If a task parameter has the same name as an inherited workflow parameter:
The system displays a prompt below the parameter: "This task parameter has the same name as a workflow parameter. The task parameter takes precedence and will override the value of the workflow parameter."
The task can still be saved and run, but the workflow parameter values are used at runtime.
To keep two separate parameters, avoid using the same name.
Step 4: Validating the Format of Parameter Values
Incorrect Reference Format for System Built-in Parameters
Exception | Example |
Incomplete double quotation marks | {{job.id
|
{{}} content is empty.
| {{}}
|
Prompt message: "Incorrect system parameter reference format will cause parameter references to become invalid."
Does not block saving. At runtime, this part is processed as a string and parameter substitution is not performed.
Referencing a Non-existent System Built-in Parameter
Exception | Example |
Misspelled parameter name | {{job.id1}}
|
Prompt: "No corresponding system built-in parameter exists."
Does not block saving. At runtime, this part is processed as a string and parameter substitution is not performed.
Step 5: Deleting Parameters
Click the delete icon at the end of the parameter row. Inherited workflow parameters cannot be deleted in the task panel. They must be deleted in the parameter configuration of the workflow configuration panel on the right.
Step 6: Saving
Click Save Task.
Supported Formats for Parameter Values
Form | Example | Applicable Level |
Static string | production
| Workflow parameter / Task parameter |
System built-in parameter | {{workflow.start_time.iso_date}}
| Workflow parameter / Task parameter |
Concatenation of multiple built-in parameters | {{workflow.start_time.year}}-{{workflow.start_time.month}}-{{workflow.start_time.day}}
| Workflow parameter / Task parameter |
Output of upstream Notebook | {{tasks.<name>.values.<key>}}
| Task parameter only |
Upstream SQL row output | {{tasks.<name>.output.first_row.<col>}}
| Task parameter only |
Parameter Description
Naming Conventions
Item | Specification |
Character Set | All languages, uppercase and lowercase letters, digits, _, and - |
Length | No more than 128 characters |
Unique | Parameter names must be unique within the same workflow; parameter names must be unique within the same task. |
Value Specifications
Item | Specification |
Length | No more than 2048 characters |
Type | String. Concatenated as a string in SQL / Notebook. |
System built-in parameter | |
Parameter Behavior When Files Are Referenced
For Notebook and SQL tasks, when a file is referenced in a task, the parameter names and values configured in the file are automatically populated into the task parameters. After population:
Parameter values can be modified. After modification, they are saved as task parameters.
Parameter changes in subsequent files will not be propagated to referenced task parameters.
If the referenced file is switched, the task parameter area will be cleared and parameters will be repopulated from the new file. Before switching files, confirm that the parameter configuration has been migrated or backed up.
Task Versions and Parameters
Task parameter changes are saved together with the task version. Both reruns and runs use the latest version of the task configuration, including parameters. For more information, see Ops Operations for Workflows and Tasks. Use Limits
Workflow parameters are automatically inherited by all tasks and cannot be modified at the task level. To define task-level specific values, define them separately in the task parameters.
In workflow run scenarios, when a task parameter has the same name as an inherited workflow parameter, the task parameter takes precedence.
Parameters support only the string type. If numeric values are required, perform an explicit conversion in the code.
The parameter value can be up to 2048 characters. Values exceeding this limit are rejected.
Workflow parameters are parsed once at startup and cannot reference task outputs ({{tasks.<name>...}}).
When parameters from an upstream task are referenced, the upstream task must have already run. For more information, see Parameter Passing. After a parameter value is changed, the currently running instance is not affected. The next run uses the new value.
FAQs
<0>Q1: If <1>dp_data_dt</1> is defined in both workflow parameters and task parameters<2>, which one is used at runtime?</2>
Task parameters. In DataBuddy, task parameters take precedence over workflow parameters.
Q2: Can task outputs be referenced in workflow parameters?
No. Workflow parameters are parsed once at workflow startup. Task output parameters ({{tasks.<name>.values.<key>}}) can only be used in task parameters. For more information, see Parameter Passing. Q3: A syntax error occurs in JSON mode and the content cannot be saved. How do I troubleshoot this?
Ensure that the entire JSON object is enclosed in {}.
Ensure that all keys and values are strings (enclosed in double quotes).
Ensure that there are no trailing commas.
Single quotes and carriage returns are not allowed in JSON. If multiple lines are required, keep the string on a single line or use \\n to escape it.
Q4: What happens if a parameter is not defined in either the workflow or the task, but is referenced in SQL as ${unknown_param}?
Debug run: A pop-up window prompts you to enter parameter values.
Scheduling run: Parameter values are replaced with empty strings, which may cause SQL syntax errors. It is recommended to define them at least in workflow parameters.
References