Configure the DolphinDB input component

Prerequisites

• You have created a DolphinDB data source. For more information, see Create a DolphinDB data source.

• The account used to configure the DolphinDB input component must have read-through permission for the data source. If the account does not have the required permissions, you must request them. For more information, see Request data source permissions.

Procedure

1. In the top menu bar of the Dataphin home page, choose Develop > Data Integration.

2. On the Data Integration page, select a Project in the top menu bar. In Dev-Prod mode, you must also select an environment.

3. In the navigation pane on the left, click Batch Pipeline. In the Batch Pipeline list, click the batch pipeline that you want to develop to open its configuration page.

4. In the upper-right corner of the page, click Component Library to open the Component Library panel.

5. In the navigation pane on the left of the Component Library panel, select Input. From the list of input components on the right, find the DolphinDB component and drag it to the canvas.

6. Click the icon on the DolphinDB input component card to open the DolphinDB Input Configuration dialog box.

7. In the DolphinDB Input Configuration dialog box, configure the following parameters.

   Parameter	Description
   Step Name	The name of the DolphinDB input component. Dataphin automatically generates a step name. You can also change the name as needed. The naming conventions are as follows: Can contain only Chinese characters, letters, underscores (_), and digits. The name can be up to 64 characters long.
   Datasource	The drop-down list displays all DolphinDB data sources and their project levels in Dataphin. This includes data sources regardless of whether you have read-through permissions. Click the icon to copy the current data source name. For a data source for which you do not have read-through permissions, click Request next to the data source to request the permissions. For more information, see Request data source permissions. If you do not have a DolphinDB data source, click New Data Source to create one. For more information, see Create a DolphinDB data source.
   Database	Select or enter the database where the table resides. If you leave this blank, the database specified during data source registration is used.
   Table	Enter a keyword to search for the table, or enter the exact table name and click Exact Match. After you select a table, the system automatically checks its status. Click the icon to copy the name of the selected table.
   Batch Read Size (Optional)	The number of data records to read at once. Configure this parameter to read data in batches instead of one record at a time. Batch reading reduces interactions with the data source, improves I/O efficiency, and lowers network latency. The default value is 8192. Enter a positive integer that is 8192 or greater.
   Input Filter (Optional)	Enter a conditional expression supported by the DolphinDB database to use as a filter condition. Note Enter only the content that follows the `where` keyword. Do not include the `where` keyword itself. You can use system global variables, such as the data timestamp `${bizdate}`.
   Output Fields	The Output Fields area displays all fields from the selected table that match the filter condition. If you do not need to output certain fields to downstream components, you can delete them. Note Data source tables do not support classification and categorization at this time. To delete a single field: To delete a small number of fields, click the icon in the Actions column to remove the unwanted fields. To delete fields in a batch: To delete many fields, click Field Management. In the Field Management dialog box, select multiple fields, click the left-shift icon to move the fields from the list of selected fields to the list of available fields, and then click OK.

8. Click OK to complete the property configuration for the DolphinDB input component.