ConnectConnect to data sourcesPostgreSQL

Connect to PostgreSQL

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Sigma supports secure connections to PostgreSQL.

This document explains how to connect your organization to a PostgreSQL database.

For information about Sigma feature compatibility with PostgreSQL connections, see Region, warehouse, and feature support.

Requirements

  • You must be assigned the Admin account type or an account type with the Manage connections feature permission enabled.
  • A PostgreSQL data warehouse
  • Sigma recommends not granting excessive permissions to the account used to connect to your data store. For example, you do not require SYSADMIN-level access.

Sigma supports PostgreSQL hosted on Google Cloud, Amazon Web Services (AWS), Microsoft Azure, Snowflake, or on premises.

Sigma does not support derivatives of PostgreSQL, such as Supabase, or “Postgres-compatible” databases such as Netezza or CockroachDB.

To use write access with PostgreSQL, PostgreSQL must be version 15 or higher. See Versioning Policy in the PostgreSQL documentation.

Create a PostgreSQL connection

Follow these basic steps to create a connection:

  1. Click the user icon at the top right of your screen. The user icon is usually composed of your initials.

  2. In the drop-down menu, select Add connection.

  3. The Add new connections page appears.

  4. In the Connection details, specify the following:

    NameEnter a Name for the new connection. Sigma displays this name in the connection list.
    TypeSelect PostgreSQL.

  5. In the Connection Credentials section, specify the following fields.

    HostThe path to your database.
    This can be a URL or an IP address depending on the configuration of your PostgreSQL instance.
    PortThe port that Sigma uses to connect to the host.
    The default port for PostgreSQL is 5432.
    UserThe username, or account, for connecting to the PostgreSQL data warehouse.
    See Create a user with the necessary data permissions for more information.
    PasswordEnter the password that corresponds to the User on the PostgreSQL account.
    To instead use a secret from your organization’s secret manager integration, turn the Use secret manager toggle on, then select your desired Secret manager and Secret.
    DatabaseThe name of the database you plan to query.
    Enable TLS(Optional) Enable or disable TLS encryption on your connection.
    Enabled by default.
    SSH Tunnel(Optional) This switch enables the SSH protocol for secure remote login. For details, see Connect through SSH.
    Disabled by default.
    If on, specify the Tunnel host and Tunnel port fields.
    Tunnel hostThe path to the tunnel server. This can be a URL or IP address. Appears only if SSH Tunnel is on.
    Tunnel portThe port where the tunnel connects. Appears only if SSH Tunnel is on.

  6. In the Connection Features section, specify the following:

    Connection timeoutThe time before timeout (or cancellation), in seconds, that Sigma waits for the query to return results.
    Default is 120, or 2 minutes.
    Maximum is 600, or 10 minutes.
    Use friendly namesThis toggle makes column names from the data source more readable.
    For example, a database column ORDER_NUMBER or OrderNumber appears as Order Number.
    On by default.

  7. In the Write Access section, decide if you require write access. See Set up write access.

    Enable write accessOff by default. Necessary for features like Input tables and Materialization.
    If on, specify the Write schema field.
    Write schemaThe schema where Sigma writes tables. Appears only if Enable write access is on.

    When you designate a schema as the write access destination, Sigma reserves it for internal write-back objects and doesn’t expose it as a data source in the connection explorer (data catalog). To avoid restricting user access to analytical data, use a dedicated write-back database or schema that doesn’t store data used for analysis and reports.

  8. After you specify all the parameters of the connection, click Create.

  9. After you successfully create your connection, Sigma displays it on the screen.

  10. To verify your connection, click Browse Connection, and then explore the visible databases and tables.

  11. Click Add Permission to grant data access for users in your organization. See Data access overview.

  12. The new connection also appears in the list of connections you have in your account.

Create a user with the necessary data permissions

When configuring your PostgreSQL connection, you can use an existing PostgreSQL user or create a new user.

If you don’t want to use an existing PostgreSQL user, create a new user for Sigma. If you want to leverage write access, create a schema for Sigma and grant all privileges to your user on that schema. Be sure to GRANT USAGE on all schemas, and GRANT SELECT on all tables that you plan to access in Sigma.

1create user sigma_user password '123';
2create schema sigma_write;
3grant all privileges on schema sigma_write to sigma_user;
4grant usage on schema public to sigma_user;
5grant select on all tables in schema public to sigma_user;

Sigma recommends using a strong username and password for your PostgreSQL user. The sample credentials shown above are for demonstration only.