/// <summary>
/// Apply the filters of the given pattern group to its result table
/// </summary>
internal static void ApplyFilters(RDFConstructQuery query, RDFPatternGroup patternGroup)
{
if (patternGroup.Patterns.Any() && patternGroup.Filters.Any())
{
DataTable filteredTable = query.PatternGroupResultTables[patternGroup].Clone();
IEnumerator rowsEnum = query.PatternGroupResultTables[patternGroup].Rows.GetEnumerator();
//Iterate the rows of the pattern group's result table
Boolean keepRow = false;
while (rowsEnum.MoveNext())
{
//Apply the pattern group's filters on the row
keepRow = true;
IEnumerator <RDFFilter> filtersEnum = patternGroup.Filters.GetEnumerator();
while (keepRow && filtersEnum.MoveNext())
{
keepRow = filtersEnum.Current.ApplyFilter((DataRow)rowsEnum.Current, false);
}
//If the row has passed all the filters, keep it in the filtered result table
if (keepRow)
{
DataRow newRow = filteredTable.NewRow();
newRow.ItemArray = ((DataRow)rowsEnum.Current).ItemArray;
filteredTable.Rows.Add(newRow);
}
}
//Save the result datatable
query.PatternGroupResultTables[patternGroup] = filteredTable;
}
}
/// <summary>
/// Get the result table of the given pattern group
/// </summary>
internal static void CombinePatterns(RDFConstructQuery query, RDFPatternGroup patternGroup)
{
if (patternGroup.Patterns.Any())
{
//Populate pattern group result table
DataTable patternGroupResultTable = RDFQueryEngine.CombineTables(query.PatternResultTables[patternGroup], false);
//Add it to the list of pattern group result tables
query.PatternGroupResultTables.Add(patternGroup, patternGroupResultTable);
//Populate its metadata
query.PatternGroupResultTables[patternGroup].TableName = patternGroup.ToString();
if (!query.PatternGroupResultTables[patternGroup].ExtendedProperties.ContainsKey("IsOptional"))
{
query.PatternGroupResultTables[patternGroup].ExtendedProperties.Add("IsOptional", patternGroup.IsOptional);
}
else
{
query.PatternGroupResultTables[patternGroup].ExtendedProperties["IsOptional"] = patternGroup.IsOptional;
}
if (!query.PatternGroupResultTables[patternGroup].ExtendedProperties.ContainsKey("JoinAsUnion"))
{
query.PatternGroupResultTables[patternGroup].ExtendedProperties.Add("JoinAsUnion", patternGroup.JoinAsUnion);
}
else
{
query.PatternGroupResultTables[patternGroup].ExtendedProperties["JoinAsUnion"] = patternGroup.JoinAsUnion;
}
}
}
/// <summary>
/// Adds the given pattern group to the query
/// </summary>
public RDFDescribeQuery AddPatternGroup(RDFPatternGroup patternGroup)
{
if (patternGroup != null)
{
if (!this.GetPatternGroups().Any(q => q.Equals(patternGroup)))
{
this.QueryMembers.Add(patternGroup);
}
}
return(this);
}
/// <summary>
/// Adds the given pattern group to the query
/// </summary>
public RDFAskQuery AddPatternGroup(RDFPatternGroup patternGroup)
{
if (patternGroup != null)
{
if (!this.PatternGroups.Exists(pg => pg.PatternGroupName.Equals(patternGroup.PatternGroupName, StringComparison.Ordinal)))
{
this.PatternGroups.Add(patternGroup);
}
}
return(this);
}
/// <summary>
/// Get the intermediate result tables of the given pattern group
/// </summary>
internal static void EvaluatePatterns(RDFConstructQuery query, RDFPatternGroup patternGroup, Object graphOrStore)
{
query.PatternResultTables[patternGroup] = new List <DataTable>();
//Iterate over the patterns of the pattern group
foreach (RDFPattern pattern in patternGroup.Patterns)
{
//Apply the pattern to the graph/store
DataTable patternResultsTable = graphOrStore is RDFGraph?RDFQueryEngine.ApplyPattern(pattern, (RDFGraph)graphOrStore)
: RDFQueryEngine.ApplyPattern(pattern, (RDFStore)graphOrStore);
//Set the name and the optionality metadata of the result datatable
patternResultsTable.TableName = pattern.ToString();
patternResultsTable.ExtendedProperties.Add("IsOptional", pattern.IsOptional);
patternResultsTable.ExtendedProperties.Add("JoinAsUnion", pattern.JoinAsUnion);
//Save the result datatable
query.PatternResultTables[patternGroup].Add(patternResultsTable);
}
}
/// <summary>
/// Prints the string representation of a pattern group
/// </summary>
internal static String PrintPatternGroup(RDFPatternGroup patternGroup, Int32 spaceIndent, Boolean skipOptional, List <RDFNamespace> prefixes)
{
String spaces = new StringBuilder().Append(' ', spaceIndent < 0 ? 0 : spaceIndent).ToString();
#region HEADER
StringBuilder result = new StringBuilder();
if (patternGroup.IsOptional && !skipOptional)
{
result.Append(" " + spaces + "OPTIONAL {\n");
spaces = spaces + " ";
}
result.Append(spaces + " {\n");
#endregion
#region MEMBERS
Boolean printingUnion = false;
List <RDFPatternGroupMember> evaluablePGMembers = patternGroup.GetEvaluablePatternGroupMembers().ToList();
RDFPatternGroupMember lastPGMember = evaluablePGMembers.LastOrDefault();
foreach (var pgMember in evaluablePGMembers)
{
#region PATTERNS
if (pgMember is RDFPattern)
{
//Union pattern
if (((RDFPattern)pgMember).JoinAsUnion)
{
if (!pgMember.Equals(lastPGMember))
{
//Begin a new Union block
printingUnion = true;
result.Append(spaces + " { " + PrintPattern((RDFPattern)pgMember, prefixes) + " }\n" + spaces + " UNION\n");
}
else
{
//End the Union block
if (printingUnion)
{
printingUnion = false;
result.Append(spaces + " { " + PrintPattern((RDFPattern)pgMember, prefixes) + " }\n");
}
else
{
result.Append(spaces + " " + PrintPattern((RDFPattern)pgMember, prefixes) + " .\n");
}
}
}
//Intersect pattern
else
{
//End the Union block
if (printingUnion)
{
printingUnion = false;
result.Append(spaces + " { " + PrintPattern((RDFPattern)pgMember, prefixes) + " }\n");
}
else
{
result.Append(spaces + " " + PrintPattern((RDFPattern)pgMember, prefixes) + " .\n");
}
}
}
#endregion
#region PROPERTY PATHS
else if (pgMember is RDFPropertyPath && pgMember.IsEvaluable)
{
//End the Union block
if (printingUnion)
{
printingUnion = false;
result.Append(spaces + " { " + PrintPropertyPath((RDFPropertyPath)pgMember, prefixes) + " }\n");
}
else
{
result.Append(spaces + " " + PrintPropertyPath((RDFPropertyPath)pgMember, prefixes) + " .\n");
}
}
#endregion
}
#endregion
#region FILTERS
patternGroup.GroupMembers.Where(m => m is RDFFilter)
.ToList()
.ForEach(f => result.Append(spaces + " " + ((RDFFilter)f).ToString(prefixes) + " \n"));
#endregion
#region FOOTER
result.Append(spaces + " }\n");
if (patternGroup.IsOptional && !skipOptional)
{
result.Append(spaces + "}\n");
}
#endregion
return(result.ToString());
}
