generate label for mysql

main_spider.py

@@ -58,7 +58,7 @@ class LightGBM(object):
         """
         path = "data/train_data/spider_data_240401.json"
         df = pd.read_json(path)
-        df.dropna(subset=['label'])
+        df = df.dropna(subset=['label'])
         labels = df['label']
         features = df.drop("label", axis=1)
         for key in self.float_columns: