Fixing an issue I found with postgres schema generator, it was applying all primary keys to all tables.

packages/server/scripts/integrations/postgres/init.sql

@@ -1,9 +1,17 @@
 SELECT 'CREATE DATABASE main'
 WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'main')\gexec
 CREATE TABLE Persons (
-    PersonID int NOT NULL PRIMARY KEY,
+    PersonID INT NOT NULL PRIMARY KEY,
     LastName varchar(255),
     FirstName varchar(255),
     Address varchar(255),
     City varchar(255)
 );
+CREATE TABLE Tasks (
+    TaskID INT NOT NULL PRIMARY KEY,
+    PersonID INT,
+    TaskName varchar(255),
+    CONSTRAINT fkPersons
+        FOREIGN KEY(PersonID)
+	    REFERENCES Persons(PersonID)
+);

packages/server/src/integrations/postgres.js

@@ -118,15 +118,18 @@ class PostgresIntegration extends Sql {
    * @param {*} datasourceId - datasourceId to fetch
    */
   async buildSchema(datasourceId) {
-    let keys = []
+    let tableKeys = {}
     try {
       const primaryKeysResponse = await this.client.query(this.PRIMARY_KEYS_SQL)
       for (let table of primaryKeysResponse.rows) {
-        keys.push(table.column_name || table.primary_key)
+        const tableName = table.table_name
+        if (!tableKeys[tableName]) {
+          tableKeys[tableName] = []
+        }
+        tableKeys[tableName].push(table.column_name || table.primary_key)
       }
     } catch (err) {
-      // TODO: this try catch method isn't right
+      tableKeys = {}
-      keys = ["id"]
     }
 
     const columnsResponse = await this.client.query(this.COLUMNS_SQL)
@@ -140,7 +143,7 @@ class PostgresIntegration extends Sql {
       if (!tables[tableName]) {
         tables[tableName] = {
           _id: buildExternalTableId(datasourceId, tableName),
-          primary: keys,
+          primary: tableKeys[tableName] || ["id"],
           name: tableName,
           schema: {},
         }