fix(redshift-driver): Use Redshift-specific schema query (cube-js#9363)

* fix(redshift-driver): Use Redshift schema query.

Fixes cube-js#3876.

* fix(redshift-driver): Use Redshift-specific schema query

---------

Co-authored-by: Emmanuel Gomez <[email protected]>

Author: 2 people

packages/cubejs-redshift-driver/src/RedshiftDriver.ts

@@ -116,6 +116,20 @@ export class RedshiftDriver extends PostgresDriver<RedshiftDriverConfiguration>
    `;
   }
 
+  /**
+   * In Redshift schemas not owned by the current user are not shown in regular information_schema,
+   * so it needs to be queried through the pg_namespace table. Because user might be granted specific
+   * permissions on the concrete schema (like CREATE tables in already existing but not owned pre-aggregation schema).
+   * @override
+   */
+  public override async createSchemaIfNotExists(schemaName: string): Promise<void> {
+    const schemaExistsQuery = `SELECT nspname FROM pg_namespace where nspname = ${this.param(0)}`;
+    const schemas = await this.query(schemaExistsQuery, [schemaName]);
+    if (schemas.length === 0) {
+      await this.query(`CREATE SCHEMA IF NOT EXISTS ${schemaName}`, []);
+    }
+  }
+
   /**
    * In Redshift external tables are not shown in regular Postgres information_schema,
    * so it needs to be queried separately.