/// <summary>
/// Performs a substring sequence query on <see cref="Trinity.Global.LocalStorage"/>. The semantics of
/// this type of query is that, given a sequence of query strings <c>q_1, q_2,...,q_n</c> in
/// <paramref name="query"/>, the match condition on a target string is that all the strings in the sequence
/// are the substrings of the target string, and the order of the substring occurrences should correspond
/// strictly to that given by <paramref name="query"/>. For example (let <c>S</c> denote the target string):
/// <example>
/// <list type="bullet">
/// <item>
/// <c>S=..q1....q2..q3{and so on}...qn...</c> is a match.
/// </item>
/// <item>
/// <c>S=.....q1q2..q4{and there are missing substrings in the sequence}...qn...</c> is not match.
/// </item>
/// <item>
/// <c>S=..q5..q3.q1{all the substrings in the sequence are present, but never in the corresponding order}...qn...</c> is not match.
/// </item>
/// </list>
/// </example>
/// The target field to query on is specified with <paramref name="query"/>, <seealso cref="t_Namespace.IndexIdentifier"/>.
/// </summary>
/// <param name="index_id">The identifier of the field that the query should be performed on.</param>
/// <param name="query">The sequence of query strings.</param>
/// <returns>
/// A list of cell ids, of which the given query string sequence is matched on the target field, or
/// an element it if it is a container of strings.
/// </returns>
public static List <long> SubstringQuery(IndexIdentifier index_id, params string[] query)
{
switch (index_id.id)
{
/*FOREACH*/
/*IF("$t_index->type == IT_SUBSTRING")*/
case t_index_id:
{
return(t_index_name_SubstringQuery(query));
}
/*END*/
/*END*/
default:
throw new Exception("The target field does not have a substring index.");
}
}
/// <summary>
/// Updates the index on the given field.
/// </summary>
/// <param name="index_id">The identifier of the field whose index should be rebuilt.</param>
public static void UpdateSubstringQueryIndex(IndexIdentifier index_id)
{
switch (index_id.id)
{
/*FOREACH*/
/*IF("$t_index->type == IT_SUBSTRING")*/
case t_index_id:
{
Log.WriteLine(LogLevel.Info, "Index: updating substring index of t_index_name");
System.Diagnostics.Stopwatch sw = System.Diagnostics.Stopwatch.StartNew();
InvertedBigramIndexer new_index;
InvertedBigramSearcher new_searcher;
ulong old_version = t_index_name_substring_index_version;
/**
* Lock the original index to prevent multiple updates
* to be executed simultaneously.
*/
lock (t_index_name_substring_index_lock)
{
/*
* If the index version has changed, it means that someone else
* has updated the index while we're blocked on the old index object.
*/
if (t_index_name_substring_index_version != old_version)
{
Log.WriteLine(LogLevel.Info, "Index: Substring index of t_index_name is already updated, stopping current action.");
break;
}
new_index = new InvertedBigramIndexer("t_index_name");
foreach (var accessor in Global.LocalStorage.t_cell_name_Accessor_Selector())
{
bool optional_not_exist = true;
META_VAR("auto", "access_chain", "$t_index->resolve_target()");
META_VAR("std::string", "field_name");
META_VAR("bool", "has_optional", "false");
META("for(auto *field : *%access_chain){");
MAP_VAR("t_field_name", "%field_name + \"Contains_\" + *field->name");
IF("field->is_optional()");
META("%has_optional = true;");
if (accessor.t_field_name)
{
END();
}
META("%field_name.append(*field->name).append(\".\");}");
IF("%has_optional");
{
optional_not_exist = false;
}
if (optional_not_exist)
{
break;
}
END();
IF("$t_index->target_field->fieldType->is_string()");
{
MAP_VAR("t_field_name", "target", MemberOf = "t_index");
new_index.AddItem(accessor.t_field_name, accessor.CellId);
}
ELSE();
{
META_VAR("std::vector<NFieldType*>*", "container_chain");
META("%container_chain = $t_index->target_field->fieldType->resolve_container_chain();");
META("%container_chain->pop_back();");
MAP_LIST("t_container_chain", "%container_chain");
META_VAR("std::string", "field_name");
META("%field_name = \"accessor.\" + *$t_index->target;");
MAP_VAR("t_field_name", "%field_name");
MAP_VAR("t_element", "std::string(\"element_\") + GetString(GET_ITERATOR_VALUE())");
META_VAR("int", "final_element", "-1");
FOREACH(); USE_LIST("t_container_chain");
foreach (var t_element in t_field_name)
/*META("%field_name = $t_element; ++%final_element;")*/
/*END*/
{
MAP_VAR("t_element", "std::string(\"element_\") + GetString(%final_element)");
new_index.AddItem((string)t_element, accessor.CellId);
}
META("delete %container_chain;");
}
END();
}
new_index.BuildIndex();
new_searcher = new InvertedBigramSearcher(true, "t_index_name");
++t_index_name_substring_index_version;
}
/* Update the index objects now. */
lock (s_IndexLock)
{
t_index_name_substring_index = new_index;
t_index_name_substring_searcher = new_searcher;
}
sw.Stop();
Log.WriteLine(LogLevel.Info, "Index: Finished updating the substring index of t_index_name. Time = {0}ms.", sw.ElapsedMilliseconds);
break;
}
/*END*/
/*END*/
default:
throw new Exception("The target field does not have a substring index.");
}
}
