public static Pair <IndexMultiKey, EventTableIndexEntryBase> FindIndexBestAvailable <T>(
IDictionary <IndexMultiKey, T> tablesAvailable,
ISet <string> keyPropertyNames,
ISet <string> rangePropertyNames,
IList <IndexHintInstruction> optionalIndexHintInstructions) where T : EventTableIndexEntryBase
{
if (keyPropertyNames.IsEmpty() && rangePropertyNames.IsEmpty())
{
return(null);
}
// determine candidates
IList <IndexedPropDesc> hashProps = new List <IndexedPropDesc>();
foreach (var keyPropertyName in keyPropertyNames)
{
hashProps.Add(new IndexedPropDesc(keyPropertyName, null));
}
IList <IndexedPropDesc> rangeProps = new List <IndexedPropDesc>();
foreach (var rangePropertyName in rangePropertyNames)
{
rangeProps.Add(new IndexedPropDesc(rangePropertyName, null));
}
var indexCandidates = EventTableIndexUtil
.FindCandidates(tablesAvailable, hashProps, rangeProps)
.Transform <IndexMultiKey, EventTableIndexEntryBase, IndexMultiKey, T>(
k => k, v => v,
k => k, v => v as T);
// handle hint
if (optionalIndexHintInstructions != null)
{
var found = EventTableIndexUtil.FindByIndexHint(indexCandidates, optionalIndexHintInstructions);
if (found != null)
{
return(GetPair(tablesAvailable, found));
}
}
// no candidates
if (indexCandidates == null || indexCandidates.IsEmpty())
{
if (Log.IsDebugEnabled)
{
Log.Debug("No index found.");
}
return(null);
}
return(GetBestCandidate(indexCandidates));
}
public static IndexMultiKey FindIndexConsiderTyping(IDictionary <IndexMultiKey, EventTableIndexMetadataEntry> tableIndexesRefCount,
IList <IndexedPropDesc> hashProps,
IList <IndexedPropDesc> btreeProps,
IList <IndexHintInstruction> optionalIndexHintInstructions)
{
if (hashProps.IsEmpty() && btreeProps.IsEmpty())
{
throw new ArgumentException("Invalid zero element list for hash and btree columns");
}
var indexCandidates = //(IDictionary<IndexMultiKey, EventTableIndexRepositoryEntry>)
EventTableIndexUtil.FindCandidates(tableIndexesRefCount, hashProps, btreeProps);
// if there are hints, follow these
if (optionalIndexHintInstructions != null)
{
var found = EventTableIndexUtil.FindByIndexHint(indexCandidates, optionalIndexHintInstructions);
if (found != null)
{
return(found);
}
}
// Get an existing table, if any, matching the exact requirement, prefer unique
var indexPropKeyMatch = EventTableIndexUtil.FindExactMatchNameAndType(tableIndexesRefCount.Keys, true, hashProps, btreeProps);
if (indexPropKeyMatch == null)
{
indexPropKeyMatch = EventTableIndexUtil.FindExactMatchNameAndType(tableIndexesRefCount.Keys, false, hashProps, btreeProps);
}
if (indexPropKeyMatch != null)
{
return(indexPropKeyMatch);
}
if (indexCandidates.IsEmpty())
{
return(null);
}
var transIndexCandidates = indexCandidates.Transform <IndexMultiKey, EventTableIndexEntryBase, IndexMultiKey, EventTableIndexMetadataEntry>(
k => k, v => v,
k => k, v => (EventTableIndexMetadataEntry)v);
return(GetBestCandidate(transIndexCandidates).First);
}