Look at the source code through Debug mode:
1. Debug the program and find the reference to the returned ResultSet
2. View the rowData in the ResultSet
3. View rows
We can see that rows is an array, which stores the data we queried (a total of 7 pieces of data in my table).
4. View elements in rows
Each element in rows corresponds to a piece of data in the database table, and the element of each element is a field of the current piece of data, and the storage method is a byte array.
