Automatically Caching Data
Automatically caching data is useful when you do not want to rebuild the cache for each query. When you query data for the first time, the provider automatically initializes and builds a cache in the background. When AutoCache = true, the provider uses the cache for subsequent query executions, resulting in faster response times.
Configuring Automatic Caching
Caching the RSSFeed Table
The following example caches the RSSFeed table in the file specified by the CacheLocation property of the connection string.
C#
String connectionString = "Cache Location=C:\\cache.db;AutoCache=true;URI=http://myservice/myfeed/;"; using (RSSConnection connection = new RSSConnection(connectionString)) { RSSCommand cmd = new RSSCommand("SELECT Guid, Author FROM RSSFeed WHERE Title = 'US'", connection); RSSDataReader rdr = cmd.ExecuteReader(); while (rdr.Read()) { Console.WriteLine("Read and cached the row with Id " + rdr["Id"]); } }
VB.NET
Dim connectionString As [String] = "Cache Location=C:\\cache.db;AutoCache=true;URI=http://myservice/myfeed/;" Using connection As New RSSConnection(connectionString) Dim cmd As New RSSCommand("SELECT Guid, Author FROM RSSFeed WHERE Title = 'US'", connection) Dim rdr As RSSDataReader = cmd.ExecuteReader() While rdr.Read() Console.WriteLine("Read and cached the row with Id " + rdr("Id")) End While End Using
Common Use Case
A common use for automatically caching data is to improve driver performance when making repeated requests to a live data source, such as building a report or creating a visualization. With auto caching enabled, repeated requests to the same data may be executed in a short period of time, but within an allowable tolerance (CacheTolerance) of what is considered "live" data.