Result Sets
You can use ResultSetMetaData to retrieve metadata about the results of a query.
The query can contain any of the following:
- Joins
- Aggregates
- Aliases
- Fully qualified names
- Generated columns
You can instantiate a ResultSetMetaData object by invoking the getMetaData method of the Statement class. A ResultSetMetaData instance is populated with data after the statement has been executed. The following query prints out the columns in the result of the query:
String connectionString = "jdbc:apacheimpala:Server=127.0.0.1;Port=21050;"; Connection conn = DriverManager.getConnection(connectionString); PreparedStatement pstmt = conn.prepareStatement("SELECT City, CompanyName AS My_CompanyName, GETDATE() FROM [CData].[Default].Customers WHERE Country = 'US'"); pstmt.executeQuery(); ResultSetMetaData rs = pstmt.getMetaData(); for(int i=1;i<=rs.getColumnCount();i++) { System.out.println(rs.getColumnName(i)); }