Dataprep upon upload

rowers/dataprep.py

@@ -156,10 +156,21 @@ def read_cols_df_sql(ids,col1,col2,col3):
     for column in columns:
         cls += column+', '
     cls = cls[:-2]
-    query = sa.text('SELECT {columns} FROM strokedata WHERE workoutid IN {ids}'.format(
-        columns = cls,
-        ids = tuple(ids),
+    if len(ids) == 0:
+        query = sa.text('SELECT {columns} FROM strokedata WHERE workoutid=0'.format(
+            columns = cls,
+            ))
+    elif len(ids) == 1:
+        query = sa.text('SELECT {columns} FROM strokedata WHERE workoutid={id}'.format(
+            id = ids[0],
+            columns = cls,
+            ))
+    else:
+        query = sa.text('SELECT {columns} FROM strokedata WHERE workoutid IN {ids}'.format(
+            columns = cls,
+            ids = tuple(ids),
         ))
+        
     df = pd.read_sql_query(query,engine)
     return df