Binding Columns for Use with Block Cursors
Because block cursors return multiple rows, applications that use them must bind an array of variables to each column instead of a single variable. These arrays are collectively known as the rowset buffers. Following are the two styles of binding:
Bind an array to each column. This is called column-wise binding because each data structure (array) contains data for a single column.
Define a structure to hold the data for an entire row and bind an array of these structures. This is called row-wise binding because each data structure contains the data for a single row.
As when the application binds single variables to columns, it calls SQLBindCol to bind arrays to columns. The only difference is that the addresses passed are array addresses, not single variable addresses. The application sets the SQL_BIND_BY_COLUMN statement attribute to specify whether it is using column-wise or row-wise binding. Whether to use column-wise or row-wise binding is largely a matter of application preference. Row-wise binding might correspond more closely to the application's layout of data, in which case it would provide better performance.
This section contains the following topics.