Update app.py

app.py

@@ -389,32 +389,49 @@ def import_zip_of_csvs_to_sqlite(db_path: str, zip_bytes: bytes) -> None:
 # ======================================================
 
 def introspect_sqlite_schema(db_path: str) -> Dict[str, Any]:
-    """
-    Devuelve:
-      - tables: {table_name: {"columns": [col1, col2, ...]}}
-      - schema_str: "table(col1, col2) ; table2(...)"
-    """
     if not os.path.exists(db_path):
         raise FileNotFoundError(f"SQLite no encontrado: {db_path}")
 
     conn = sqlite3.connect(db_path)
     cur = conn.cursor()
+
+    # --- TABLAS
     cur.execute("SELECT name FROM sqlite_master WHERE type='table';")
     tables = [row[0] for row in cur.fetchall()]
 
-    tables_info: Dict[str, Dict[str, List[str]]] = {}
+    tables_info = {}
+    foreign_keys = []  # <--- nuevo
+
     parts = []
 
     for t in tables:
+        # Columnas
         cur.execute(f"PRAGMA table_info('{t}');")
-        rows = cur.fetchall()  # cid, name, type, notnull, dflt_value, pk
+        rows = cur.fetchall()
         cols = [r[1] for r in rows]
         tables_info[t] = {"columns": cols}
+
+        # Relaciones FK
+        cur.execute(f"PRAGMA foreign_key_list('{t}');")
+        fks = cur.fetchall()
+        for (id, seq, table, from_col, to_col, on_update, on_delete, match) in fks:
+            foreign_keys.append({
+                "from_table": t,
+                "from_column": from_col,
+                "to_table": table,
+                "to_column": to_col
+            })
+
         parts.append(f"{t}(" + ", ".join(cols) + ")")
 
     conn.close()
     schema_str = " ; ".join(parts) if parts else "(empty_schema)"
-    return {"tables": tables_info, "schema_str": schema_str}
+
+    return {
+        "tables": tables_info,
+        "foreign_keys": foreign_keys,  # <--- nuevo
+        "schema_str": schema_str
+    }
 
 
 def execute_sqlite(db_path: str, sql: str) -> Dict[str, Any]: