/// <summary>
/// <paramref name="cmd"/> 를 비동기 방식으로 실행하여, Scalar 값을 반환하는 <see cref="Task{Object}"/>를 빌드합니다.
/// </summary>
/// <param name="db">DAAB의 SQLite 용 Database 인스턴스</param>
/// <param name="cmd">실행할 cmd 인스턴스</param>
/// <param name="parameters">Command Parameters</param>
/// <returns>결과 Scalar 값을 가지는 Task의 인스턴스</returns>
public static Task <object> ExecuteScalarAsync(this SQLiteDatabase db, SQLiteCommand cmd, params IAdoParameter[] parameters)
{
cmd.ShouldNotBeNull("cmd");
if (IsDebugEnabled)
{
log.Debug("cmd.ExecuteScalar 를 비동기 방식으로 실행합니다. CommandText=[{0}], Parameters=[{1}]",
cmd.CommandText, parameters.CollectionToString());
}
var newConnectionCreated = false;
if (cmd.Connection == null)
{
cmd.Connection = SQLiteTool.CreateSQLiteConnection(db, ref newConnectionCreated);
}
if (parameters != null)
{
AdoTool.SetParameterValues(db, cmd, parameters);
}
return
(Task.Factory
.StartNew(() => cmd.ExecuteScalar(), TaskCreationOptions.PreferFairness)
.ContinueWith(task => {
if (newConnectionCreated)
{
AdoTool.ForceCloseConnection(cmd);
}
return task;
},
TaskContinuationOptions.ExecuteSynchronously)
.Unwrap());
}
/// <summary>
/// <paramref name="cmd"/> 를 이용하여, <see cref="Task{SqlDataReader}"/>를 반환받습니다.
/// 받환받은 DataReader는 꼭 Dispose() 해 주어야 Connection이 닫힙니다.
/// </summary>
/// <param name="db">DAAB의 SQLite 용 Database 인스턴스</param>
/// <param name="cmd">실행할 cmd 인스턴스</param>
/// <param name="parameters">Command Parameters</param>
/// <returns></returns>
public static Task <SQLiteDataReader> ExecuteReaderAsync(this SQLiteDatabase db, SQLiteCommand cmd,
params IAdoParameter[] parameters)
{
cmd.ShouldNotBeNull("cmd");
if (IsDebugEnabled)
{
log.Debug("cmd.ExecuteReader 를 비동기 방식으로 실행합니다. CommandText=[{0}], Parameters=[{1}]",
cmd.CommandText, parameters.CollectionToString());
}
var newConnectionCreated = false;
if (cmd.Connection == null)
{
cmd.Connection = SQLiteTool.CreateSQLiteConnection(db, ref newConnectionCreated);
}
if (parameters != null)
{
AdoTool.SetParameterValues(db, cmd, parameters);
}
var commandBehavior = newConnectionCreated ? CommandBehavior.CloseConnection : CommandBehavior.Default;
return(Task.Factory.StartNew(() => cmd.ExecuteReader(commandBehavior), TaskCreationOptions.PreferFairness));
}