Database Log-Couldn & #39; t read row 0, col, rowcol

Database Log's Couldn't read row 0, col, rowcol

Today, I wrote code and the log reported a very strange error. The information in CursorWindow is Couldn't read row 0, col-1

This error is generally because the specified column is not displayed when you query data from sqlite, or the data type does not match. It is best to develop good programming habits to avoid these low-level errors, such as writing "cursor. getString (cursor. getColumnIndex (" xxx ")" instead of "cursor. getString (3 )".

Another possibility is db = dbHelper. getReadableDatabase (). In fact, db = dbHelper. getWritableDatabase ();

This error occurs when the constructor db = dbHelper. getWritableDatabase (); after initialization, you forget to change the data to be queried later.