Data Management (DMS) allows you to view the technical metadata, business metadata, and management metadata of a table on the details page of the table. This helps you fully understand and efficiently use the data of the table.

Background information

DMS provides the metadata of a table to help developers and business staff understand the relationships between upstream and downstream data and the purpose of the data in the table. This saves time for understanding data and allows users to find the required data in a quick and precise manner. This also improves development and management efficiency.

The following list describes the types of metadata that DMS provides for a table:
  • Technical metadata: the physical information about the table in the database, such as the instance and database to which the table belongs, table name, comments, fields, indexes, character set, number of rows, capacity, data lineage, task information, and data quality.
  • Business metadata: the business information that is used to describe and manage the table, such as the tags, category, and description of the table, the description of each field, and usage notes.
  • Management metadata: the information that is used to manage the table in DMS, such as the permissions, control fields, and owner of the table.

Prerequisites

  • The database instance to be managed is a relational database or a data warehouse. For more information, see Supported database types.
  • The database instance for which you want to enable metadata access control is managed in Security Collaboration mode. For more information, see Control modes.

  • One of the following conditions are met:
    • You are a DMS administrator or a database administrator (DBA) in DMS. Alternatively, you assume the schema read-only role. For more information, see System roles.
    • You are the owner or the DBA of the database instance that you want to manage. For more information, see Modify database instances.
    • You have the permissions to query, change, or export the data of the database instance that you want to manage or a table in the database instance. For more information, see View owned permissions.

Procedure

  1. Go to the DMS console V5.0.
  2. Go to the details page of a table. You can use one of the following methods to go to the details page of a table:
    • Navigate to the details page of a table from the SQL Console page
      1. In the top navigation bar, choose SQL Console > SQL Console.
      2. In the Please select the database first dialog box, enter a keyword to search for a database instance, select the database instance from the search results, and then click Confirm.
      3. In the extended feature section that is in the upper-right corner of the SQL Console page, click the Table List icon icon.
      4. Find the table that you want to view, move the pointer over More in the Actions column, and then select View Table Details. The Details panel appears.
    • Search for the table that you want to view
      1. In the top navigation bar, click Home. In the search box, enter the name of the table that you want to view.
      2. In the search results, click the Table option. Find the table that you want to view and click Details on the right to go to the Tables page.
      Tables page
  3. On the Tables page, perform relevant operations as required.
    Table 1. GUI of the Tables page
    Section Description
    Table overview
    • Character Set: the character set of the table.
    • Rows: the number of rows in the table.
    • Capacity (MB): the storage space occupied by the table.
    • Environment: the environment type of the database instance to which the table belongs, such as the development or test environment. For more information, see Change the environment type of an instance.
    • DB Information: the database instance to which the table belongs.
    • Permission: the permissions that you have on the table.
    • Data Owner: the owner of the table.
    • Tag: the tags of the table. You can add one or more phrases as tags for classification.
    • Description: the comments on the table.
    • Business Description: the business description of the table. The description can be up to 1,000 characters in length. This can help relevant users understand the purpose of the table.
    • Category: the category of the table. You can select a category for the table in a category tree. For more information, see Use the category feature.
    • Subscribe: You can click Subscribe to subscribe to the notifications about the schema change of the table. The schema change may be caused by tickets for schema design and data change in DMS, or SQL statements that are used to change the schema on the SQLConsole tab. For more information about notification methods, see Manage notification rules.
    Basic information
    • Field Information:

      The Field Information tab displays the basic information about each field in the table, such as the field name, data type, description, sensitivity level, sensitivity level source, and business description.

      Note If you are the owner of the table, a DMS administrator, or a DBA, you can modify the business description of each field. To modify the business description of a field, find the field and double-click the description in the Business Description column.
      You can also perform the following operations:
      • Generate a SELECT Statement: View the SELECT statement that is used to query all fields in the table.
      • Export Schema: View the schema of the table in the format of a data dictionary. You can export the schema in the form of a Word, Excel, or PDF file.
      • Generate a DDL Statement: View the complete DDL statement that is used to create the table.
      • Sensitivity level adjustment: Change the sensitivity level of one or more fields. For more information, see Adjust the sensitivity level of one or more fields.
      • Code Generator: Generate code in various formats.
    • Index:

      The Index tab displays the name, type, included columns, and remarks for each index.

    • Row-level control:

      The Row Control tab displays the information about control fields. To view the details of a control field, click Control value details in the Actions column.

    Data Lineage

    When you use the task orchestration feature to synchronize and process the data of the table, the data flows.

    The Data Lineage tab displays how data flows from tables to tables or from fields to fields. This tab helps you fully understand upstream and downstream data. This can help you resolve issues about data governance, such as repeated data processing and unauthorized use of data. In addition, data lineage also helps you minimize the impact that is caused by data changes.

    The following sample SQL statements can generate table lineage or field lineage:
    • Table lineage: INSERT INTO table1 SELECT * FROM table2;
    • Field lineage: INSERT INTO table1 (col1, col2) SELECT col3 , col4 FROM table2;
    In the preceding sample SQL statements, the data flows from the table2 table to the table1 table. This indicates that table2 is the upstream of table1, and table1 is the downstream of table2.

    To view the upstream and downstream of a table or a field, click the Icon used to view data lineage icon on the left and right sides of the table or field. The upstream data is displayed on the left side, and the downstream data is displayed on the right side.

    Historical Versions On the Historical Versions tab, you can view the schema versions of the table. You can also perform the following operations:
    • Preview script: Preview the SQL script that is used to generate the schema version.
    • Table structure comparison: Synchronize the schema version to another database, or compare the schema version with a schema version in another database. For more information, see Synchronize schemas.
    • Structural recovery: Synchronize the schema version that you want to restore to an empty database. For more information, see Initialize empty databases.
    Task Information If you use the task orchestration feature to write data to the table, you can view the information about each task, such as the task name, start time, duration, and end time.
    You can also perform the following operations:
    • Click Code to view the code of the task on the task orchestration page.
    • Click Log to view the operational logs of the task.
    Data Preview On the Data Preview tab, you can view the first 50 data entries in the table.
    Note To view data entries, you must have the permissions to query the data of the table or the database instance to which the table belongs. For more information, see View owned permissions.
    Data quality On the Data quality tab, you can create quality rules for the table. Then, you can use the quality rules on the task orchestration page to check whether the data of the table is valid. This improves data quality. For more information, see Check the data quality.
    Instructions for Use On the Instructions for Use tab, you can enter the usage notes and additional information about the table that help other users understand and use the table. The Markdown syntax is supported.
    Note All users can view the information that you enter, but only DMS administrators, DBAs, or table owner can modify the information.