/// <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);
}
/// <summary>
/// Applies the query to the given data source
/// </summary>
internal RDFSelectQueryResult ApplyToDataSource(RDFDataSource dataSource)
{
if (dataSource != null)
{
switch (dataSource)
{
case RDFGraph graph:
return(this.ApplyToGraph(graph));
case RDFStore store:
return(this.ApplyToStore(store));
case RDFFederation federation:
return(this.ApplyToFederation(federation));
case RDFSPARQLEndpoint sparqlEndpoint:
return(this.ApplyToSPARQLEndpoint(sparqlEndpoint));
}
}
return(new RDFSelectQueryResult());
}
/// <summary>
/// Applies the query to the given datasource
/// </summary>
internal RDFDescribeQueryResult ApplyToDataSource(RDFDataSource datasource)
{
this.PatternGroupResultTables.Clear();
this.PatternResultTables.Clear();
RDFDescribeQueryResult describeResult = new RDFDescribeQueryResult(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: Describe the terms from the result table
DataTable describeResultTable = new DataTable(this.ToString());
if (datasource.IsFederation())
{
#region TrueFederations
foreach (var store in (RDFFederation)datasource)
{
describeResultTable.Merge(RDFQueryEngine.DescribeTerms(this, store, queryResultTable), true, MissingSchemaAction.Add);
}
#endregion
}
else
{
describeResultTable = RDFQueryEngine.DescribeTerms(this, datasource, queryResultTable);
}
//Step 6: Apply the modifiers of the query to the result table
describeResult.DescribeResults = RDFQueryEngine.ApplyModifiers(this, describeResultTable);
}
else
{
//In this case the only chance to proceed is to have resources in the describe terms,
//which will be used to search for S-P-O data. Variables are ignored in this scenario.
if (this.DescribeTerms.Any(dt => dt is RDFResource))
{
//Step 1: Describe the terms from the result table
DataTable describeResultTable = new DataTable(this.ToString());
if (datasource.IsFederation())
{
#region TrueFederations
foreach (var store in (RDFFederation)datasource)
{
describeResultTable.Merge(RDFQueryEngine.DescribeTerms(this, store, new DataTable()), true, MissingSchemaAction.Add);
}
#endregion
}
else
{
describeResultTable = RDFQueryEngine.DescribeTerms(this, datasource, new DataTable());
}
//Step 2: Apply the modifiers of the query to the result table
describeResult.DescribeResults = RDFQueryEngine.ApplyModifiers(this, describeResultTable);
}
}
return(describeResult);
}
