Connect Tableau to Hologres for visual analytics - Hologres

Prerequisites

Before you begin, ensure that you have:

A running Hologres instance with a database created
The public endpoint and port of the instance (available in the Network Information section of the Hologres console)
Your Alibaba Cloud AccessKey ID and AccessKey secret (available in AccessKey Management)
Tableau Desktop installed (download from the Tableau website)

Connect Tableau Desktop to Hologres

Step 1: Configure the TDC file (recommended)

A Tableau Datasource Customization (TDC) file optimizes query compatibility and performance for the Hologres connection. Skipping this step may result in degraded query performance or unexpected behavior.

Download the TDC file.

Copy the TDC file to the appropriate directory:

Tableau product	Directory
Tableau Desktop	`Documents\My Tableau Repository\Datasources`
Tableau Server on Windows	`ProgramData\Tableau\Tableau Server\data\tabsvc\vizqlserver\Datasources` (on each server node)
Tableau Server on Linux	`/var/opt/tableau/tableau_server/data/tabsvc/vizqlserver/Datasources/` (on each server node)

Restart Tableau Desktop and Tableau Server.

For more details about TDC files, see Tableau Help.

Step 2: Connect to Hologres

Open Tableau Desktop.
In the left navigation pane, under Connect > To a Server, select PostgreSQL

Enter the connection details:

Parameter	Description
Server	The public endpoint of the Hologres instance. Find it in the Network Information section of the Hologres console.
Port	The port of the Hologres instance. Find it in the Network Information section of the Hologres console.
Database	The name of your Hologres database.
Authentication	Select Username and Password.
Username	Your Alibaba Cloud AccessKey ID. Get it from AccessKey Management.
Password	Your Alibaba Cloud AccessKey secret. Get it from AccessKey Management.
Require SSL	Leave unselected.

(Optional) Click Initial SQL and enter the following command to tag queries sent from Tableau. This makes it easier to identify Tableau-originated queries in Hologres query logs.
```
SET application_name='tableau'
```
Click Logon.

After connecting, you can build visualizations directly on your Hologres tables. See Tableau tutorials to get started.

Publish to Tableau Server

If your team uses Tableau Server to share and manage reports, publish your workbook from Tableau Desktop.

Step 1: Install Tableau Server

Download and install Tableau Server from the Tableau website.

Step 2: Sign in to Tableau Server from Tableau Desktop

Open Tableau Desktop. From the top menu, choose Server > Logon.
Enter the address of your Tableau Server and click Connect.
Enter your Tableau Server username and password, then click Logon.

Step 3: Publish the workbook

From the top menu, choose Server > Publish Workbook.

In the Publish Workbook dialog box, configure the following parameters:

Parameter	Description
Project	Select the destination project.
Name	Enter a name for the workbook.
Tags	Add tags to help users find this workbook. Separate multiple tags with a comma or space.
Permissions	Accept the default project settings.
Data Sources	Select the authentication method for the Hologres data source connection. Choose Embed password so that any user who can view the workbook can see the data without entering credentials separately. Choose Prompt user if you want each viewer to authenticate individually.

Publish Workbook

Click Publish.

The workbook is now available in Tableau Server.

FAQ

TIMESTAMPTZ data shows the wrong time in Tableau

This happens because Hologres uses the PRC time zone by default, while Tableau uses UTC. Set an Initial SQL statement to align the time zones.

First-time connection: When creating the data connection, click Initial SQL and enter:
```
SET TIME ZONE "PRC";
```
Existing connection: Open the data source in Tableau Desktop, click Initial SQL, enter the same command, and click OK. Then click the icon to apply the settings.

This setting applies only to the specific data source you configure it on.

Tableau is applying unexpected type conversions to time-type columns

Set the column to TIMESTAMP or TIMESTAMPTZ when you create the table in Hologres. This avoids secondary transformations in Tableau, which can introduce unnecessary field type conversions.