public Tuple <TSource, TTarget1, TTarget2> Scalar <TSource, TTarget1, TTarget2>(FromExpression <TSource> fromCondition, WhereExpression <TSource> whereCondition, TransactionContext transContext)
where TSource : DatabaseEntity, new()
where TTarget1 : DatabaseEntity, new()
where TTarget2 : DatabaseEntity, new()
{
IList <Tuple <TSource, TTarget1, TTarget2> > result = Retrieve <TSource, TTarget1, TTarget2>(fromCondition, whereCondition, transContext);
if (result == null || result.Count == 0)
{
return(null);
}
if (result.Count > 1)
{
throw new DatabaseException($"Scalar retrieve return more than one result. From:{fromCondition.ToString()}, Where:{whereCondition.ToString()}");
//_logger.LogCritical(0, "retrieve result not one, but many." + typeof(TSource).FullName, null);
//return null;
}
return(result[0]);
}
public Task <Tuple <TSource, TTarget1, TTarget2> > ScalarAsync <TSource, TTarget1, TTarget2>(FromExpression <TSource> fromCondition, WhereExpression <TSource> whereCondition, TransactionContext transContext)
where TSource : DatabaseEntity, new()
where TTarget1 : DatabaseEntity, new()
where TTarget2 : DatabaseEntity, new()
{
return(RetrieveAsync <TSource, TTarget1, TTarget2>(fromCondition, whereCondition, transContext)
.ContinueWith(t => {
IList <Tuple <TSource, TTarget1, TTarget2> > lst = t.Result;
if (lst == null || lst.Count == 0)
{
return null;
}
if (lst.Count > 1)
{
throw new DatabaseException($"Scalar retrieve return more than one result. From:{fromCondition.ToString()}, Where:{whereCondition.ToString()}");
//_logger.LogCritical(0, "retrieve result not one, but many." + typeof(TSource).FullName, null);
//return null;
}
return lst[0];
}, TaskScheduler.Default));
}
public T Scalar <T>(SelectExpression <T> selectCondition, FromExpression <T> fromCondition, WhereExpression <T> whereCondition, TransactionContext transContext)
where T : DatabaseEntity, new()
{
IList <T> result = Retrieve <T>(selectCondition, fromCondition, whereCondition, transContext);
if (result == null || result.Count == 0)
{
return(null);
}
if (result.Count > 1)
{
//_logger.LogCritical(0, "retrieve result not one, but many." + typeof(T).FullName, null);
throw new DatabaseException($"Scalar retrieve return more than one result. Select:{selectCondition.ToString()}, From:{fromCondition.ToString()}, Where:{whereCondition.ToString()}");
}
return(result[0]);
}
public Task <T> ScalarAsync <T>(SelectExpression <T> selectCondition, FromExpression <T> fromCondition, WhereExpression <T> whereCondition, TransactionContext transContext)
where T : DatabaseEntity, new()
{
return(RetrieveAsync <T>(selectCondition, fromCondition, whereCondition, transContext)
.ContinueWith(t => {
IList <T> lst = t.Result;
if (lst == null || lst.Count == 0)
{
return default;
}
if (lst.Count > 1)
{
throw new DatabaseException($"Scalar retrieve return more than one result. Select:{selectCondition.ToString()}, From:{fromCondition.ToString()}, Where:{whereCondition.ToString()}");
//_logger.LogCritical(0, "retrieve result not one, but many." + typeof(T).FullName, null);
//return default;
}
return lst[0];
}, TaskScheduler.Default));
}