With Hasura and Sequin, you can read data from and write data to Salesforce, HubSpot, and Airtable using GraphQL. This guide will walk you through setting up Sequin, connecting Hasura Cloud, configuring your schema, and querying your data. Connect Salesforce, Stripe, HubSpot, and more to Hasura

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Setup Sequin

To use Hasura with Sequin, you need to sync to a self-hosted database. A Sequin-hosted demo database isn’t configured with the permissions required to connect to Hasura.
Step 1: Login to Sequin and select the source you want to sync. If you need more details, follow the step-by-step setup guide for your source. Step 2: Once you’ve connected your source, select which objects and properties you would like to sync to your database. You can always change this later. Step 3: Connect your database to Sequin. Click the Connect button in the destination section of the Sequin dashboard. Then, enter your database connection details and set the name of the schema you want to sync your data to. If you need more detail, read our guide on connecting a database. Step 5: Click Create to start your sync. Sequin will now create a new schema in your database and start syncing your data to it. You can monitor the progress of your sync in the Sequin dashboard. Within a minute or two, you’ll see your tables and data appear in your database. You can now setup Hasura.

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Setup Hasura

Step 1: Create a new Hasura Cloud project. If you don’t have one already, you can sign up for a free account. Step 2: Connect your database to Hasura. You can do this by selecting Postgres and then clicking the Connect Existing Database button in the Hasura dashboard. Enter your database connection details and click Connect Database. If you need more details, read the Hasura docs. Step 3: Once Hasura connects to your database, it will appear in the Data Manager. Next, you can configure Hasura to track the tables in your database. Select your database and the schema containing the tables you want to track. Then, click the Track button next to each table you want to query via Hasura. Do this for both your public schema and your Sequin schema. Track tables in Hasura
You don’t need to track Sequin system tables that start with _sync.

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Configure relationships

Hasura uses relationships to join tables together when executing GraphQL queries. Because your Sequin schema doesn’t contain foreign keys, you’ll manually configure relationships in the Hasura dashboard or using the Hasura CLI. Step 1: To configure relationships in the Hasura dashboard, select the table you want to define a relationship for in the Data Manager, click the Relationships tab, and then click the Add Relationship button. Step 2: Give the relationship a name (e.g., deal_associations), select the table you want to join to, and then select the columns you want to join on. Then click the Create Relationship button: Build relationships in Hasura Depending on which source you are syncing, you’ll need to define relationships differently. Below are the primary relationship types you’ll need to define:

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Direct relationships

For sources like Salesforce and Stripe, you’ll often create a relationship between two tables by simply mapping the primary key of one table to the foreign key of the other table. For example, if you want to join the account table to the opportunity table, you would map the account_id column in the opportunity table to the id column in the account table. ERD for a direct relationship To give you ultimate querying options in GraphQL, you’ll create a relationship on each side of this join:
  1. On the account table you’ll create an object relationship between account.id and opportunity.account_id.
  2. On the opportunity table you’ll create an array relationship between opportunity opportunity.account_id and account.id.

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Join table relationships

For sources like HubSpot, you’ll often need to create a relationship between two tables using an associations join table. For example, if you want to join the deal table to the contact table, you’ll sync a join table called associations_contact_deal that contains the relationship between deal_id and contact_id. Then, you would map the deal_id column in the associations_contact_deal join table to the id column in the deal table and the contact_id column in the associations_contact_deal table to the id column in the contact table. ERD for a join table relationship In this scenario, you’ll create a total of four relationships:
  1. On the associations_contact_deal table you’ll create an object relationship between associations_contact_deal.contact_id and contact.id. You can call this associations_contact.
  2. You’ll then create the other end of the first relationship. On the contact table you’ll create an object relationship between associations_contact_deal.contact_id and contact.id. You can call this contact_associations.
You’ll then repeat this process for the deal table:
  1. On the associations_contact_deal table you’ll create a object relationship between associations_contact_deal.deal_id and deal.id. You can call this associations_deal.
  2. You’ll then create the other end of the relationship. On the deal table you’ll create an object relationship between associations_contact_deal.deal_id and deal.id. You can call this deal_associations.

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Views and generated columns

Hasura and Sequin support Postgres views and generated columns. You can use these features to create custom views and columns in your database to simplify querying patterns in GraphQL. For instance, you can create a view called deals_and_contacts that joins your HubSpot deal table to your contact table via the associations_contact_deal join table. The view can contain just the columns you need: 
create view deals_and_contacts as
select
    contact.id as "contact_id",
    contact.firstname,
    contact.lastname,
    deal.id as "deal_id",
    deal.dealname,
    deal.stage
from hubspot.contact
    join hubspot.associations_contact_deal on contact.id = associations_contact_deal.contact_id
    join hubspot.deal on associations_contact_deal.deal_id = deal.id;
In Hasura, you can then track this view to include it in your GraphQL schema - simplifying the query pattern. Alternatively, you may need to use a generated column to ensure joins in Hasura function correctly. For example, let’s say you want to join your public.users table with your salesforce.contact table on the users.id and contact.user_id columns. However, the users.id column is type int4 and the contact.user_id column is type varchar. You can create a generated column on the contact table that casts the user_id column to int4 in a new column called _user_id: 
ALTER TABLE salesforce.contact
ADD COLUMN _user_id int4
GENERATED ALWAYS AS (CAST(user_id AS int4)) STORED;
In Hasura, you’ll then define a relationship between the users table and the contact table using the _user_id column.

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Build

Sequin and Hasura are now configured to work together. You can now use all the power of Hasura to query your database using GraphQL. A query to return the the state of a deal for one of your users might look like this: 
query MyQuery {
  users(where: { id: { _eq: 1 } }) {
    first_name
    last_name
    email
    user_to_contact {
      contact_to_association {
        association_to_deal {
          id
          dealname
          stage
        }
      }
    }
  }
}
From here, you can use Hasura’s event triggers, actions, and authentication to rapidly build your application.