我有两个表Raw_data和CoCode。我想要一个访问查询来删除Raw_data表中的所有行，这些行在CoCode表中没有公司代码。
答案 0 :(得分：0)
您可以使用 @RequiresApi(api = Build.VERSION_CODES.KITKAT)
void writeStreamToFile(Context mContext, Uri mUri,String ext) {
if (mUri == null) {
return;
}
String[] filePathColumn = {MediaStore.Images.Media.DATA};
Cursor cursor = mContext.getContentResolver().query(mUri, filePathColumn, null, null, null);
String mCurrentPath = null;
if (cursor != null && cursor.moveToFirst()) {
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
mCurrentPath = cursor.getString(columnIndex);
cursor.close();
}
if (TextUtils.isEmpty(mCurrentPath)) {
mCurrentPath = mUri.getPath();
}
File storageDir = mContext.getExternalFilesDir(Environment.DIRECTORY_DOCUMENTS);
InputStream inputStream = null;
try {
inputStream = mContext.getContentResolver().openInputStream(mUri);
File file = File.createTempFile("pptFiles", ext, storageDir);
try (OutputStream output = new FileOutputStream(file)) {
byte[] buffer = new byte[4 * 1024]; // or other buffer size
int read;
while ((read = inputStream.read(buffer)) != -1) {
output.write(buffer, 0, read);
}
output.flush();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
inputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
。假设带有代码的列在NOT EXISTS中名为code，在Raw_data中名称为id：
CoCode