fix sql reader byte without base64
fix sql reader byte without base64

qiniu/logkit,andrewei1316/logkit,qiniu/logkit,wonderflow/logkit-1,qiniu/logkit,andrewei1316/logkit,andrewei1316/logkit,qiniu/logkit,qiniu/logkit,wonderflow/logkit-1,wonderflow/logkit-1,wonderflow/logkit-1,andrewei1316/logkit