private void Init()
{
_start = 0;
_end = 0;
// for instance, only manage index for one field query using 'equal'
if (_classInfo.HasIndex() && _query.HasCriteria() &&
((IInternalConstraint)_query.GetCriteria()).CanUseIndex())
{
var fields = _query.GetAllInvolvedFields();
if (fields.IsNullOrEmpty())
{
_useIndex = false;
}
else
{
var fieldIds = GetAllInvolvedFieldIds(fields);
_classInfoIndex = _classInfo.GetIndexForAttributeIds(fieldIds);
if (_classInfoIndex != null)
{
_useIndex = true;
}
}
}
// Keep the detail
_details = GetDetails();
}
/// <summary>
/// Take the fields of the index and take value from the query
/// </summary>
/// <param name="index"> The index </param>
/// <returns> The key of the index </returns>
protected virtual IOdbComparable ComputeIndexKey(ClassInfoIndex index)
{
var attributesNames = ClassInfo.GetAttributeNames(index.AttributeIds);
var constraint = Query.GetCriteria();
var values = ((IInternalConstraint)constraint).GetValues();
return(IndexTool.BuildIndexKey(index.Name, values, attributesNames));
}
