public override Boolean Optimize(QueryParameters queryParameters, QueryStack queryElementsStack)
{
Boolean treeChanged = false;
if (queryElementsStack.HasElementOnPeek(ElementType.WHERE) &&
queryElementsStack.FindLastAncestorOnPeekByType(ElementType.WHERE_OPERATION) is OperationComperision &&
((AbstractComposite)queryElementsStack.FindLastAncestorOnPeekByType(ElementType.WHERE_OPERATION)).HasDescendant(ElementType.LITERAL))
{
var className = (ClassName)queryElementsStack.FindLastAncestorOnPeekByType(ElementType.CLASS_NAME);
queryParameters.IndexMechanism.GetIndexesForAttribute(className.Value, Name)
?.ToList()
.ForEach(p => {
if (className.Indexes == null)
{
className.Indexes = new Dictionary <int, string>();
}
if (!className.Indexes.ContainsKey(p.Key))
{
className.Indexes.Add(p.Key, p.Value);
treeChanged = true;
}
});
}
return(treeChanged);
}
public override bool Optimize(QueryParameters parameters, QueryStack queryStack)
{
var index = default(KeyValuePair <int, string>);
if (Indexes != null && Indexes.Count > 0)
{
index = Indexes
.OrderByDescending(p => parameters.IndexMechanism.GetPessimisticObjectFindCost(p.Key, Cardinality(parameters)))
.First();
}
if (!index.Equals(Index) && Cardinality(parameters) > parameters.SettingsManager.MaxNumberObjectsFullScan)
{
Index = index;
var selectStatement = (SelectStatement)queryStack.FindLastAncestorOnPeekByType(ElementType.SELECT);
selectStatement.Index = index;
return(true);
}
return(false);
}
