/// <summary>
/// Applies the query to the given datasource
/// </summary>
internal RDFConstructQueryResult ApplyToDataSource(RDFDataSource datasource)
{
this.PatternGroupResultTables.Clear();
this.PatternResultTables.Clear();
RDFConstructQueryResult constructResult = new RDFConstructQueryResult(this.ToString());
if (this.PatternGroups.Any())
{
//Iterate the pattern groups of the query
var fedPatternResultTables = new Dictionary <RDFPatternGroup, List <DataTable> >();
foreach (var patternGroup in this.PatternGroups)
{
//Step 1: Get the intermediate result tables of the current pattern group
if (datasource.IsFederation())
{
#region TrueFederations
foreach (var store in (RDFFederation)datasource)
{
//Step FED.1: Evaluate the patterns of the current pattern group on the current store
RDFQueryEngine.EvaluatePatterns(this, patternGroup, store);
//Step FED.2: Federate the patterns of the current pattern group on the current store
if (!fedPatternResultTables.ContainsKey(patternGroup))
{
fedPatternResultTables.Add(patternGroup, this.PatternResultTables[patternGroup]);
}
else
{
fedPatternResultTables[patternGroup].ForEach(fprt =>
fprt.Merge(this.PatternResultTables[patternGroup].Single(prt => prt.TableName.Equals(fprt.TableName, StringComparison.Ordinal)), true, MissingSchemaAction.Add));
}
}
this.PatternResultTables[patternGroup] = fedPatternResultTables[patternGroup];
#endregion
}
else
{
RDFQueryEngine.EvaluatePatterns(this, patternGroup, datasource);
}
//Step 2: Get the result table of the current pattern group
RDFQueryEngine.CombinePatterns(this, patternGroup);
//Step 3: Apply the filters of the current pattern group to its result table
RDFQueryEngine.ApplyFilters(this, patternGroup);
}
//Step 4: Get the result table of the query
DataTable queryResultTable = RDFQueryEngine.CombineTables(this.PatternGroupResultTables.Values.ToList(), false);
//Step 5: Fill the templates from the result table
DataTable filledResultTable = RDFQueryEngine.FillTemplates(this, queryResultTable);
//Step 6: Apply the modifiers of the query to the result table
constructResult.ConstructResults = RDFQueryEngine.ApplyModifiers(this, filledResultTable);
}
return(constructResult);
}