También miré en esto, y después de comparar el método SqlDataAdapter.Fill con las funciones SqlDataReader.Load, descubrí que el método SqlDataAdapter.Fill es más del doble de rápido con los conjuntos de resultados que he estado usando
Código utilizado:
[TestMethod]
public void SQLCommandVsAddaptor()
{
long AdapterFillLargeTableTime, readerLoadLargeTableTime, AdapterFillMediumTableTime, readerLoadMediumTableTime, AdapterFillSmallTableTime, readerLoadSmallTableTime, AdapterFillTinyTableTime, readerLoadTinyTableTime;
string LargeTableToFill = "select top 10000 * from FooBar";
string MediumTableToFill = "select top 1000 * from FooBar";
string SmallTableToFill = "select top 100 * from FooBar";
string TinyTableToFill = "select top 10 * from FooBar";
using (SqlConnection sconn = new SqlConnection("Data Source=.;initial catalog=Foo;persist security info=True; user id=bar;password=foobar;"))
{
// large data set measurements
AdapterFillLargeTableTime = MeasureExecutionTimeMethod(sconn, LargeTableToFill, ExecuteDataAdapterFillStep);
readerLoadLargeTableTime = MeasureExecutionTimeMethod(sconn, LargeTableToFill, ExecuteSqlReaderLoadStep);
// medium data set measurements
AdapterFillMediumTableTime = MeasureExecutionTimeMethod(sconn, MediumTableToFill, ExecuteDataAdapterFillStep);
readerLoadMediumTableTime = MeasureExecutionTimeMethod(sconn, MediumTableToFill, ExecuteSqlReaderLoadStep);
// small data set measurements
AdapterFillSmallTableTime = MeasureExecutionTimeMethod(sconn, SmallTableToFill, ExecuteDataAdapterFillStep);
readerLoadSmallTableTime = MeasureExecutionTimeMethod(sconn, SmallTableToFill, ExecuteSqlReaderLoadStep);
// tiny data set measurements
AdapterFillTinyTableTime = MeasureExecutionTimeMethod(sconn, TinyTableToFill, ExecuteDataAdapterFillStep);
readerLoadTinyTableTime = MeasureExecutionTimeMethod(sconn, TinyTableToFill, ExecuteSqlReaderLoadStep);
}
using (StreamWriter writer = new StreamWriter("result_sql_compare.txt"))
{
writer.WriteLine("10000 rows");
writer.WriteLine("Sql Data Adapter 100 times table fill speed 10000 rows: {0} milliseconds", AdapterFillLargeTableTime);
writer.WriteLine("Sql Data Reader 100 times table load speed 10000 rows: {0} milliseconds", readerLoadLargeTableTime);
writer.WriteLine("1000 rows");
writer.WriteLine("Sql Data Adapter 100 times table fill speed 1000 rows: {0} milliseconds", AdapterFillMediumTableTime);
writer.WriteLine("Sql Data Reader 100 times table load speed 1000 rows: {0} milliseconds", readerLoadMediumTableTime);
writer.WriteLine("100 rows");
writer.WriteLine("Sql Data Adapter 100 times table fill speed 100 rows: {0} milliseconds", AdapterFillSmallTableTime);
writer.WriteLine("Sql Data Reader 100 times table load speed 100 rows: {0} milliseconds", readerLoadSmallTableTime);
writer.WriteLine("10 rows");
writer.WriteLine("Sql Data Adapter 100 times table fill speed 10 rows: {0} milliseconds", AdapterFillTinyTableTime);
writer.WriteLine("Sql Data Reader 100 times table load speed 10 rows: {0} milliseconds", readerLoadTinyTableTime);
}
Process.Start("result_sql_compare.txt");
}
private long MeasureExecutionTimeMethod(SqlConnection conn, string query, Action<SqlConnection, string> Method)
{
long time; // know C#
// execute single read step outside measurement time, to warm up cache or whatever
Method(conn, query);
// start timing
time = Environment.TickCount;
for (int i = 0; i < 100; i++)
{
Method(conn, query);
}
// return time in milliseconds
return Environment.TickCount - time;
}
private void ExecuteDataAdapterFillStep(SqlConnection conn, string query)
{
DataTable tab = new DataTable();
conn.Open();
using (SqlDataAdapter comm = new SqlDataAdapter(query, conn))
{
// Adapter fill table function
comm.Fill(tab);
}
conn.Close();
}
private void ExecuteSqlReaderLoadStep(SqlConnection conn, string query)
{
DataTable tab = new DataTable();
conn.Open();
using (SqlCommand comm = new SqlCommand(query, conn))
{
using (SqlDataReader reader = comm.ExecuteReader())
{
// IDataReader Load function
tab.Load(reader);
}
}
conn.Close();
}
Resultados:
10000 rows:
Sql Data Adapter 100 times table fill speed 10000 rows: 11782 milliseconds
Sql Data Reader 100 times table load speed 10000 rows: 26047 milliseconds
1000 rows:
Sql Data Adapter 100 times table fill speed 1000 rows: 984 milliseconds
Sql Data Reader 100 times table load speed 1000 rows: 2031 milliseconds
100 rows:
Sql Data Adapter 100 times table fill speed 100 rows: 125 milliseconds
Sql Data Reader 100 times table load speed 100 rows: 235 milliseconds
10 rows:
Sql Data Adapter 100 times table fill speed 10 rows: 32 milliseconds
Sql Data Reader 100 times table load speed 10 rows: 93 milliseconds
Para problemas de rendimiento, usar el método SqlDataAdapter.Fill es mucho más eficiente. Entonces, a menos que quieras dispararte en el pie, usa eso. Funciona más rápido para conjuntos de datos grandes y pequeños.