bug fix: pandas dtypes

transport/sql.py

@@ -185,6 +185,7 @@ class BigQuery:
         self.credentials = service_account.Credentials.from_service_account_file(path)
         self.dataset = _args['dataset'] if 'dataset' in _args else None
         self.path = path
+        self.dtypes = _args['dtypes'] if 'dtypes' in _args else None
     def meta(self,**_args):
         """
         This function returns meta data for a given table or query with dataset/table properly formatted
@@ -225,7 +226,13 @@ class BQReader(BigQuery,Reader) :
             SQL += " LIMIT "+str(_args['limit'])
         if (':dataset' in SQL or ':DATASET' in SQL)  and self.dataset:
             SQL = SQL.replace(':dataset',self.dataset).replace(':DATASET',self.dataset)
-        return pd.read_gbq(SQL,credentials=self.credentials,dialect='standard') if SQL else None
+        _info = {'credentials':self.credentials,'dialect':'standard'}
+        if 'dtypes' in _args  or self.dtypes :
+            self.dtypes = _args ['dtypes'] if 'dtypes' in self.dtypes else None
+            if self.dtypes :
+                _info['dtypes'] = self.dtypes
+        return pd.read_gbq(SQL,*_info) if SQL else None    
+        # return pd.read_gbq(SQL,credentials=self.credentials,dialect='standard') if SQL else None
 class BQWriter(BigQuery,Writer):
     lock = Lock()
     def __init__(self,**_args):
@@ -237,7 +244,7 @@ class BQWriter(BigQuery,Writer):
 
     def write(self,_info,**_args) :
         try:
-            if self.parallel :
+            if self.parallel or 'lock' in _args :
                 BQWriter.lock.acquire()
             self._write(_info,**_args)
         finally: