e273. creating an updatable result set.txt

这里面包含了一百多个JAVA源文件

An updatable result set allows modification to data in a table through the result set. If the database does not support updatable result sets, the result sets returned from executeQuery() will be read-only. To get updatable results, the Statement object used to create the result sets must have the concurrency type ResultSet.CONCUR_UPDATABLE. 
The query of an updatable result set must specify the primary key as one of the selected columns and select from only one table. For some drivers, `SELECT * FROM my_table' will return a read-only result set, so make sure that you specify the column names. 

See also e272 Determining If a Database Supports Updatable Result Sets. 

    try {
        // Create a statement that will return updatable result sets
        Statement stmt = connection.createStatement(
            ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
    
        // Primary key col_string must be specified so that the result set is updatable
        ResultSet resultSet = stmt.executeQuery("SELECT col_string FROM my_table");
    } catch (SQLException e) {
    }