Hologres:Connect to HoloWeb

Procedure

1. Log on to the Hologres Management Console.

2. In the navigation pane on the left of the top menu bar, select the desired region.

3. You can click Go to HoloWeb to go to the HoloWeb development page.

4. Connect to a Hologres instance.

   1. On the Metadata Management tab, click Instances.

   2. In the Instances dialog box, configure the parameters as required and click OK.

      Parameter	Description	Required
      Network type	Public Network: Supported in China (Shanghai), China (Shenzhen), China (Beijing), China (Hangzhou), China (Zhangjiakou), Singapore, China (Hong Kong), Malaysia (Kuala Lumpur), Indonesia (Jakarta), and US (Silicon Valley). An instance with the icon uses the public network type. VPC: Only supported in the region where HoloWeb is logged on. An instance with the icon uses the VPC type. You cannot edit its details or delete it.	No
      Instance name	Select an instance that has been created under your current account. Note After purchasing an instance, HoloWeb may take time to load the instance information. If the instance name does not appear immediately, manually configure connection details such as the Domain Name to connect to the target instance.	No
      Name	If you select an Instance Name, the Name field defaults to the selected instance name. You can also customize the connection name.	Yes
      Description	A description for the connection.	No
      Domain name	The network domain name of the Hologres instance. You can go to the instance details page in the Hologres Management Console and obtain the domain name from the Network Information section. If you select an Instance Name, the system automatically fills in the corresponding Domain Name. You can also enter the domain name manually.	Yes
      Port	The network port of the Hologres instance. You can navigate to the Hologres Management Console instance details page and obtain the port from the Network Information. If you select an Instance Name, the system automatically fills in the corresponding Port. You can also enter the port number manually.	Yes
      Logon method	Password-free Logon: Log on directly using your current account without entering a username or password. Password Logon: Enter the username and password of your account or another account to log on.	Yes
      Username	This parameter is required only if you set logon method to logon with account and password. The AccessKey ID for the current account. You can obtain your AccessKey ID from AccessKey Management.	No
      Password	This parameter is required only if you set logon method to logon with account and password. Enter the AccessKey secret of your current account.	No
      Test connectivity	Check whether the connection succeeds: If The test is successful. appears, the connection succeeded. If The test failed. appears, the connection failed.	No
      Log on after connecting	Choose whether to log on to the instance after connecting. Yes: The instance logs on and appears in the logged-on instances list on the left. No: The instance appears in the not logged-on instances list on the left.	Yes

5. Optional. Create a database.

   After you purchase a Hologres instance, a database named postgres is automatically created. This database is allocated a few resources and is used only for management purposes. You can create a database based on your business requirements.

   Note

   If you have created a database, skip this step and proceed to the next step.

   1. On the Metadata Management > Create Database.

      You can also click Instances Connected in the left-side navigation pane of the Metadata Management tab. Right-click your Hologres instance and select New Database.

   2. In the Create Database dialog box, configure the parameters and click OK.

      Parameter	Description
      Instance Name	The name of the logged-on instance where the current database resides is displayed by default.
      Database Name	Name the current database. Note The configured database name must be unique.
      Access Policy	Configure permissions for the database as needed. For more information about access policies, see: SPM SLPM standard PostgreSQL authorization model
      Log on Immediately	Yes: Use the created database directly after logging on. No: Log on to the database before using it.

6. Create an SQL query.

   After you connect HoloWeb to a Hologres instance, you can use standard PostgreSQL statements to analyze data on the SQL Editor tab.

   1. On the SQL Editor tab, click the icon.

      You can also right-click My SQL query in the left-side navigation pane and select Create SQL Query. For more information, see Manage an SQL query task.

   2. On the Ad-hoc Query tab, select an instance from the Instance Name drop-down list and a database from the Database drop-down list, enter the following sample statements in the SQL editor, and then click Running.

      BEGIN;
      CREATE TABLE nation (
       n_nationkey bigint NOT NULL,
       n_name text NOT NULL,
       n_regionkey bigint NOT NULL,
       n_comment text NOT NULL,
      PRIMARY KEY (n_nationkey)
      );
      CALL SET_TABLE_PROPERTY('nation', 'bitmap_columns', 'n_nationkey,n_name,n_regionkey');
      CALL SET_TABLE_PROPERTY('nation', 'dictionary_encoding_columns', 'n_name,n_comment');
      CALL SET_TABLE_PROPERTY('nation', 'time_to_live_in_seconds', '31536000');
      COMMIT;
      
      INSERT INTO nation VALUES
      (11,'zRAQ', 4,'nic deposits boost atop the quickly final requests?  quickly regula'),
      (22,'RUSSIA', 3  ,'requests against the platelets use never according to the quickly regular pint'),
      (2,'BRAZIL',  1 ,'y alongside of the pending deposits. carefully special packages are about the ironic forges. slyly special '),
      (5,'ETHIOPIA',  0 ,'ven packages wake quickly. regu'),
      (9,'INDONESIA', 2  ,'slyly express asymptotes. regular deposits haggle slyly. carefully ironic hockey players sleep blithely. carefull'),
      (14,'KENYA',  0  ,'pending excuses haggle furiously deposits. pending, express pinto beans wake fluffily past t'),
      (3,'CANADA',  1 ,'eas hang ironic, silent packages. slyly regular packages are furiously over the tithes. fluffily bold'),
      (4,'EGYPT', 4 ,'y above the carefully unusual theodolites. final dugouts are quickly across the furiously regular d'),
      (7,'GERMANY', 3 ,'l platelets. regular accounts x-ray: unusual, regular acco'),
      (20 ,'SAUDI ARABIA',  4 ,'ts. silent requests haggle. closely express packages sleep across the blithely');
      
      SELECT * FROM nation;

      Note

      The table names and field names in SQL statements are not case-sensitive. If you want to search for a table with an exactly matched name, you need to enclose the name of the table in double quotation marks (") in SQL statements.

   3. View the execution result of the statements in the Operational Logs section.

      

7. Create a foreign table to accelerate queries on MaxCompute data.

   Hologres is seamlessly integrated with MaxCompute at the underlying layer. You can create foreign tables in Hologres to accelerate queries of MaxCompute data. To create a foreign table in the HoloWeb console, perform the following steps:

   Note

   • Make sure that a MaxCompute project is created, a table is created in the project, and data is written to the table. For more information, see Create a MaxCompute project. You can use one of the following methods to create a table and write data:

     1. Add a MaxCompute data source in the DataWorks console. Then, create a table and write data to the table.

     2. Use the MaxCompute client to create a table and write data to the table. For more information, see Use the MaxCompute client.

   • You can accelerate queries on data in MaxCompute and OSS data lakes only after you log on to a database in the HoloWeb console.

   1. On the Metadata Management > MaxCompute Query Acceleration > Create Foreign Table.

   2. On the Create MaxCompute External Table tab, select an acceleration method, configure other parameters, and then click Submit.

      Entire Project

      Category	Parameter	Description
      Acceleration Method	Select an acceleration method.	Valid values: Entire Project Selected Tables Single Table Select Entire Project.
      MaxCompute Data Source	Project Name	The name of the MaxCompute project.
      	Schema Name	The name of the schema in which the MaxCompute table resides. If your MaxCompute project uses the two-layer model, this parameter is not displayed by default. If your MaxCompute project uses the three-layer model, you can specify an authorized schema for this parameter. For information about the schema feature, see Schema-related operations.
      Destination Table Position	Holo Schema	The name of the schema. You can select the default schema named public or a custom schema.
      Advanced Settings	Processing Rule for Table Name Conflicts	Valid values: Ignore Conflicts and Continue Creating Tables Change Table Names Report Error and Create No Table
      	Processing Rule for Unsupported Data Types	Valid values: Report Error and Stop Import Ignore and Skip Table of Unsupported Fields

      Selected Tables

      Category	Parameter	Description
      Acceleration Method	Select an acceleration method.	Valid values: Entire Project Selected Tables Single Table Select Selected Tables.
      MaxCompute Data Source	Project Name	The name of the MaxCompute project.
      	Schema Name	The name of the schema in which the MaxCompute table resides. If your MaxCompute project uses the two-layer model, this parameter is not displayed by default. If your MaxCompute project uses the three-layer model, you can specify an authorized schema for this parameter. For information about the schema feature, see Schema-related operations.
      Destination Table Position	Holo Schema	The name of the schema. You can select the default schema named public or a custom schema.
      Advanced Settings	Processing Rule for Table Name Conflicts	Valid values: Ignore Conflicts and Continue Creating Tables Change Table Names Report Error and Create No Table
      	Processing Rule for Unsupported Data Types	Valid values: Report Error and Stop Import Ignore and Skip Table of Unsupported Fields
      	Search	A maximum of 200 tables can be displayed when you search for source tables. Excess tables are not displayed.

      Single Table

      Category	Parameter	Description
      Acceleration Method	Select an acceleration method.	Valid values: Entire Project Selected Tables Single Table Select Single Table.
      MaxCompute Data Source	Project Name	The name of the MaxCompute project.
      	Schema Name	The name of the schema in which the MaxCompute table resides. If your MaxCompute project uses the two-layer model, this parameter is not displayed by default. If your MaxCompute project uses the three-layer model, you can specify an authorized schema for this parameter. For information about the schema feature, see Schema-related operations.
      	Table Name	The name of the table in the schema of MaxCompute. You can enter a table name prefix to perform a fuzzy match.
      Destination Hologres Table	Schema	The name of the schema. You can select the default schema named public or a custom schema.
      	Table Name	The name of the Hologres table used for query acceleration.
      	Destination Table Description	The description of the Hologres table used for query acceleration.

   3. After you create the foreign table, find the instance where the foreign table resides from the Instances Connected list in the left-side navigation pane on the Metadata Management Double-click the foreign table. On the tab that appears, click Data preview to preview the data in the MaxCompute table for which queries are accelerated.