public override object Read(CompactBinaryReader reader)
{
ISerializationSurrogate decimalSurrogate = TypeSurrogateSelector.GetSurrogateForType(typeof(decimal), null);
AverageResult result = new AverageResult();
result.Sum = (decimal)decimalSurrogate.Read(reader);
result.Count = (decimal)decimalSurrogate.Read(reader);
return result;
}
internal override void Execute(QueryContext queryContext, Predicate nextPredicate)
{
if(ChildPredicate!=null)
ChildPredicate.Execute(queryContext, nextPredicate);
queryContext.Tree.Reduce();
CacheEntry entry = null;
decimal sum = 0;
if (queryContext.Tree.LeftList.Count > 0)
{
foreach (string key in queryContext.Tree.LeftList)
{
CacheEntry cacheentry = queryContext.Cache.GetEntryInternal(key, false);
object attribValue = queryContext.Index.GetAttributeValue(key, AttributeName, cacheentry.IndexInfo);
if (attribValue != null)
{
Type type = attribValue.GetType();
if ((type == typeof(bool)) || (type == typeof(DateTime)) || (type == typeof(string)) || (type == typeof(char)))
throw new Exception("AVG can only be applied to integral data types.");
sum += Convert.ToDecimal(attribValue);
}
}
AverageResult avgResult = new AverageResult();
avgResult.Sum = sum;
avgResult.Count = queryContext.Tree.LeftList.Count;
//put the count and the sum
base.SetResult(queryContext, AggregateFunctionType.AVG, avgResult);
}
else
{
base.SetResult(queryContext, AggregateFunctionType.AVG, null);
}
}
public void Compile(QueryResultSet resultSet)
{
if (!this._isInitialized)
{
Initialize(resultSet);
return;
}
switch (this.Type)
{
case QueryType.AggregateFunction:
switch ((AggregateFunctionType)this.AggregateFunctionResult.Key)
{
case AggregateFunctionType.SUM:
decimal a;
decimal b;
object thisVal = this.AggregateFunctionResult.Value;
object otherVal = resultSet.AggregateFunctionResult.Value;
Nullable<decimal> sum = null;
if (thisVal == null && otherVal != null)
{
sum = (decimal)otherVal;
}
else if (thisVal != null && otherVal == null)
{
sum = (decimal)thisVal;
}
else if (thisVal != null && otherVal != null)
{
a = (decimal)thisVal;
b = (decimal)otherVal;
sum = a + b;
}
if (sum != null)
{
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.SUM, sum);
}
else
{
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.SUM, null);
}
break;
case AggregateFunctionType.COUNT:
a = (decimal)this.AggregateFunctionResult.Value;
b = (decimal)resultSet.AggregateFunctionResult.Value;
decimal count = a + b;
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.COUNT, count);
break;
case AggregateFunctionType.MIN:
IComparable thisValue = (IComparable)this.AggregateFunctionResult.Value;
IComparable otherValue = (IComparable)resultSet.AggregateFunctionResult.Value;
IComparable min = thisValue;
if (thisValue == null && otherValue != null)
{
min = otherValue;
}
else if (thisValue != null && otherValue == null)
{
min = thisValue;
}
else if (thisValue == null && otherValue == null)
{
min = null;
}
else if (otherValue.CompareTo(thisValue) < 0)
{
min = otherValue;
}
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.MIN, min);
break;
case AggregateFunctionType.MAX:
thisValue = (IComparable)this.AggregateFunctionResult.Value;
otherValue = (IComparable)resultSet.AggregateFunctionResult.Value;
IComparable max = thisValue;
if (thisValue == null && otherValue != null)
{
max = otherValue;
}
else if (thisValue != null && otherValue == null)
{
max = thisValue;
}
else if (thisValue == null && otherValue == null)
{
max = null;
}
else if (otherValue.CompareTo(thisValue) > 0)
{
max = otherValue;
}
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.MAX, max);
break;
case AggregateFunctionType.AVG:
thisVal = this.AggregateFunctionResult.Value;
otherVal = resultSet.AggregateFunctionResult.Value;
AverageResult avg = null;
if (thisVal == null && otherVal != null)
{
avg = (AverageResult)otherVal;
}
else if (thisVal != null && otherVal == null)
{
avg = (AverageResult)thisVal;
}
else if (thisVal != null && otherVal != null)
{
AverageResult thisResult = (AverageResult)thisVal;
AverageResult otherResult = (AverageResult)otherVal;
avg = new AverageResult();
avg.Sum = thisResult.Sum + otherResult.Sum;
avg.Count = thisResult.Count + otherResult.Count;
}
if (avg != null)
{
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.AVG, avg);
}
else
{
this.AggregateFunctionResult = new DictionaryEntry(AggregateFunctionType.AVG, null);
}
break;
}
break;
case QueryType.SearchKeys:
if (this.SearchKeysResult == null)
this.SearchKeysResult = resultSet.SearchKeysResult;
else
if (resultSet.SearchKeysResult != null)
this.SearchKeysResult.AddRange(resultSet.SearchKeysResult);
break;
case QueryType.SearchEntries:
if (this.SearchEntriesResult == null)
this.SearchEntriesResult = resultSet.SearchEntriesResult;
else
{
IDictionaryEnumerator ide = resultSet.SearchEntriesResult.GetEnumerator();
while (ide.MoveNext())
{
this.SearchEntriesResult[ide.Key]=ide.Value;
}
}
break;
}
}