new file: backend/src/controllers/schemaController.ts

new file:   backend/src/migrations/008_add_database_schemas.sql
	modified:   backend/src/routes/sqlInterface.ts
	modified:   frontend/package.json
	modified:   frontend/src/App.tsx
	modified:   frontend/src/components/Sidebar.tsx
	new file:   frontend/src/pages/DatabaseSchema.tsx
	modified:   frontend/src/services/api.ts

frontend/src/services/api.ts

@@ -187,4 +187,42 @@ export const sqlInterfaceApi = {
     api.post<SqlQueryResult>('/workbench/execute', { database_id: databaseId, query }),
 };
 
+// Schema API
+export interface ColumnInfo {
+  name: string;
+  type: string;
+  nullable: boolean;
+  default_value: string | null;
+  is_primary: boolean;
+  comment: string | null;
+}
+
+export interface ForeignKey {
+  column: string;
+  references_table: string;
+  references_column: string;
+  constraint_name: string;
+}
+
+export interface TableInfo {
+  name: string;
+  schema: string;
+  comment: string | null;
+  columns: ColumnInfo[];
+  foreign_keys: ForeignKey[];
+}
+
+export interface SchemaData {
+  tables: TableInfo[];
+  updated_at: string;
+}
+
+export const schemaApi = {
+  getSchema: (databaseId: string) =>
+    api.get<{ success: boolean; data: SchemaData }>(`/workbench/schema/${databaseId}`),
+
+  refreshSchema: (databaseId: string) =>
+    api.post<{ success: boolean; data: SchemaData }>(`/workbench/schema/${databaseId}/refresh`),
+};
+
 export default api;