Database access, regardless of two kinds: connection type, breakaway
A connection type: Use SqlConnectio
Access to the database and the connection process between the SqlConnection the formula is the Open (), Close ()
Data reading using SqlDataReader
Pros: take up less memory, data is read when the database has been and remains connected for a small amount of data when high efficiency.
Disadvantages: need to maintain the established database connection, if the user access to large, may lead to an abnormal connection pool, the connection complex.
Second, the breakaway: the SqlDataAdapter used (data adapter)
Advantages: i.e. before breakaway connection attributes configuration, switching the connection no longer, reducing the frequency of access to the server, connection pool does not take up too much resources, open a data set locally for storing the read data, modify when the changes do not only for the local data sets directly modify the data server.
Disadvantages: This mode is the one-time read the data in memory, so the large amount of data can be very time consuming memory
