/// <summary>
/// Adds the future query to the waiting queries list on this context.
/// </summary>
/// <param name="query">The future query.</param>
public void AddQuery(IFutureQuery query)
{
if (query == null)
{
throw new ArgumentNullException("query");
}
FutureQueries.Add(query);
}
/// <summary>
/// Gets the data command for this query.
/// </summary>
/// <param name="dataContext">The data context to get the command from.</param>
/// <returns>The requested command object.</returns>
protected override DbCommand GetCommand(System.Data.Linq.DataContext dataContext)
{
IFutureQuery futureQuery = this;
var source = futureQuery.Query;
// get static count method
FindCountMethod();
// create count expression
var genericCount = _countMethod.MakeGenericMethod(new[] { source.ElementType });
var expression = Expression.Call(null, genericCount, source.Expression);
return(dataContext.GetCommand(expression));
}
/// <summary>
/// Sets the underling value after the query has been executed.
/// </summary>
/// <param name="dataContext">The data context to translate the results with.</param>
/// <param name="reader">The <see cref="DbDataReader" /> to get the result from.</param>
protected virtual void SetResult(ObjectContext dataContext, DbDataReader reader)
{
IsLoaded = true;
try
{
IFutureQuery futureQuery = this;
var source = futureQuery.Query;
var q = source as ObjectQuery;
if (q == null)
{
throw new InvalidOperationException("The future query is not of type ObjectQuery.");
}
// create execution plan
dynamic queryProxy = new DynamicProxy(q);
// ObjectQueryState
dynamic queryState = queryProxy.QueryState;
// ObjectQueryExecutionPlan
dynamic executionPlan = queryState.GetExecutionPlan(null);
// ShaperFactory
dynamic shaperFactory = executionPlan.ResultShaperFactory;
// Shaper<T>
dynamic shaper = shaperFactory.Create(reader, dataContext, dataContext.MetadataWorkspace,
MergeOption.AppendOnly, false, true, false);
var list = new List <T>();
IEnumerator <T> enumerator = shaper.GetEnumerator();
while (enumerator.MoveNext())
{
list.Add(enumerator.Current);
}
_result = list;
// translate has issue with column names not matching
//var resultSet = dataContext.Translate<T>(reader);
//_result = resultSet.ToList();
}
catch (Exception ex)
{
Exception = ex;
}
}
/// <summary>
/// Sets the underling value after the query has been executed.
/// </summary>
/// <param name="dataContext">The data context to translate the results with.</param>
/// <param name="reader">The <see cref="DbDataReader" /> to get the result from.</param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
/// <exception cref="InvalidOperationException">The future query is not of type ObjectQuery.</exception>
protected virtual async Task SetResultAsync(ObjectContext dataContext, DbDataReader reader, CancellationToken cancellationToken = default(CancellationToken))
{
_isLoaded = true;
try
{
IFutureQuery futureQuery = this;
var source = futureQuery.Query;
var q = source as ObjectQuery;
if (q == null)
{
throw new InvalidOperationException("The future query is not of type ObjectQuery.");
}
// create execution plan
dynamic queryProxy = new DynamicProxy(q);
// ObjectQueryState
dynamic queryState = queryProxy.QueryState;
// ObjectQueryExecutionPlan
dynamic executionPlan = queryState.GetExecutionPlan(null);
// ShaperFactory
dynamic shaperFactory = executionPlan.ResultShaperFactory;
// Shaper<T>
dynamic shaper = shaperFactory.Create(reader, dataContext, dataContext.MetadataWorkspace,
MergeOption.AppendOnly, false, true, false);
var list = new List <T>();
// Shaper<T> GetEnumerator method return IDbEnumerator<T>, which implements publicly accessible IDbAsyncEnumerator<T>
IDbAsyncEnumerator <T> enumerator = shaper.GetEnumerator();
while (await enumerator.MoveNextAsync(cancellationToken).ConfigureAwait(false))
{
list.Add(enumerator.Current);
}
_result = list;
// translate has issue with column names not matching
//var resultSet = dataContext.Translate<T>(reader);
//_result = resultSet.ToList();
}
catch (Exception ex)
{
Exception = ex;
}
}
/// <summary>
/// Gets the data command for this query.
/// </summary>
/// <param name="dataContext">The data context to get the command from.</param>
/// <returns>The requested command object.</returns>
protected virtual FuturePlan GetPlan(ObjectContext dataContext)
{
IFutureQuery futureQuery = this;
var source = futureQuery.Query;
var q = source as ObjectQuery;
if (q == null)
{
throw new InvalidOperationException("The future query is not of type ObjectQuery.");
}
var plan = new FuturePlan
{
CommandText = q.ToTraceString(),
Parameters = q.Parameters
};
return(plan);
}
/// <summary>
/// Adds the future query to the waiting queries list on this context.
/// </summary>
/// <param name="query">The future query.</param>
public void AddQuery(IFutureQuery query)
{
if (query == null)
throw new ArgumentNullException("query");
FutureQueries.Add(query);
}
