Question - How Can I Get Data From Multiple Resultsets?
Answer -
With certain database systems, a stored procedure can return multiple result sets, multiple update counts, or some combination of both. Also, if you are providing a user with the ability to enter any SQL statement, you don't know if you are going to get a ResultSet or an update count back from each statement, without analyzing the contents. The Statement.execute() method helps in these cases.
Method Statement.execute() returns a boolean to tell you the type of response:
true indicates next result is a ResultSet
Use Statement.getResultSet to get the ResultSet
false indicates next result is an update count
Use Statement.getUpdateCount to get the update count
false also indicates no more results
Update count is -1 when no more results (usually 0 or positive)
After processing each response, you use Statement.getMoreResults to check for more results, again returning a boolean. The following demonstrates the processing of multiple result sets:
boolean result = stmt.execute(" ... ");
int updateCount = stmt.getUpdateCount();
while (result || (updateCount != -1)) {
if(result) {
ResultSet r = stmt.getResultSet();
// process result set
} else if(updateCount != -1) {
// process update count
}
result = stmt.getMoreResults();
updateCount = stmt.getUpdateCount();
}