A dbCursor is required for each SQL statement that is to be processed. VORTEX automatically maps a logical cursor to an actual database cursor which allows an application to allocate many more cursors than the underlying database actually can support.
A dbCursor has 2 close states: soft or hard. Normally an application closes a cursor in soft mode, which means that the cursor is simply marked as closed on the client. When the dbCursor is used again VORTEX determines if the cursor can be re-used without having to open (re-parse) the database cursor. Reuse is a big performance boost. In a client/server environment the cursor cache becomes even more important as it cuts down the number of network roundtrips needed.
A LRU algorithm is used when soft-closed cursors need to be re-mapped.
Sets (bind) a String parameter. Uses ``'' to pass a NULL value to the database.
Sets (bind) an Integer parameter. Uses ``'' to pass a NULL value to the database.
Sets (bind) a Blob parameter. Uses ``'' to pass a NULL value to the database.
Returns cursor number and state used for later synchronize operation.
Returns true if no more (fetch) data is available. This call is only valid after a fetch().
Returns the number of output columns. This call is only valid after a fetch().
Returns ($errorcode,$dbDescriptor) for an output column. This call is only valid after a fetch().