PostgreSQL: Fix error on panel when toggling sqlDatasourceDatabaseSelection feature (#106965)

Co-authored-by: Zoltán Bedi <zoltan.bedi@gmail.com>

packages/grafana-sql/src/datasource/SqlDatasource.ts

@@ -154,7 +154,7 @@ export abstract class SqlDatasource extends DataSourceWithBackend<SQLQuery, SQLO
 
   private checkForDatabaseIssue(request: DataQueryRequest<SQLQuery>) {
     // If the datasource is Postgres and there is no default database configured - either never configured or removed - return a database issue.
-    if (this.type === 'postgres' && !this.preconfiguredDatabase) {
+    if (this.type === 'grafana-postgresql-datasource' && !this.preconfiguredDatabase) {
       return `You do not currently have a default database configured for this data source. Postgres requires a default
              database with which to connect. Please configure one through the Data Sources Configuration page, or if you
              are using a provisioning file, update that configuration file with a default database.`;
@@ -170,7 +170,11 @@ export abstract class SqlDatasource extends DataSourceWithBackend<SQLQuery, SQLO
       if (!!this.preconfiguredDatabase) {
         for (const target of request.targets) {
           // Test for database configuration change only if query was made in `builder` mode.
-          if (target.editorMode === EditorMode.Builder && target.dataset !== this.preconfiguredDatabase) {
+          if (
+            target.editorMode === EditorMode.Builder &&
+            target.dataset &&
+            target.dataset !== this.preconfiguredDatabase
+          ) {
             return `The configuration for this panel's data source has been modified. The previous database used in this panel's
                    saved query is no longer available. Please update the query to use the new database option.
                    Previous query parameters will be preserved until the query is updated.`;