private List <IndexData> ParseIndexesAndGetReadyToMerge()
{
var indexes = new List <IndexData>();
foreach (var kvp in _indexDefinitions)
{
var index = kvp.Value;
var indexData = new IndexData(index)
{
IndexName = index.Name,
OriginalMaps = index.Maps
};
indexes.Add(indexData);
if (index.Type == IndexType.MapReduce || index.Maps.Count > 1)
{
indexData.IsMapReduceOrMultiMap = true;
continue;
}
var visitor = new IndexVisitor(indexData);
var map = SyntaxFactory.ParseExpression(indexData.OriginalMaps.FirstOrDefault()).NormalizeWhitespace();
map.Accept(visitor);
}
return(indexes);
}
private bool CanMergeIndexes(IndexData other, IndexData current)
{
if (current.IndexName == other.IndexName)
{
return(false);
}
if (current.NumberOfFromClauses > 1)
{
return(false);
}
if (current.NumberOfSelectClauses > 1)
{
return(false);
}
if (current.HasWhere)
{
return(false);
}
if (current.HasGroup)
{
return(false);
}
if (current.HasOrder)
{
return(false);
}
if (current.HasLet)
{
return(false);
}
var currentFromExpression = current.FromExpression as MemberAccessExpressionSyntax;
var otherFromExpression = other.FromExpression as MemberAccessExpressionSyntax;
if (currentFromExpression != null || otherFromExpression != null)
{
if (currentFromExpression == null || otherFromExpression == null)
{
return(false);
}
if (currentFromExpression.Name.Identifier.ValueText != otherFromExpression.Name.Identifier.ValueText)
{
return(false);
}
}
return(CompareIndexFieldOptions(other, current));
}
private static bool AreSelectClausesCompatible(IndexData x, IndexData y)
{
foreach (var pair in x.SelectExpressions)
{
if (y.SelectExpressions.TryGetValue(pair.Key, out ExpressionSyntax expressionValue) == false)
{
continue;
}
// for the same key, they have to be the same
var ySelectExpr = ExtractValueFromExpression(expressionValue);
var xSelectExpr = ExtractValueFromExpression(pair.Value);
if (xSelectExpr != ySelectExpr)
{
return(false);
}
}
return(true);
}
private static List <string> CheckForUnsuitableIndexForMerging(IndexData indexData)
{
var failComments = new List <string>();
if (indexData.Index.Type == IndexType.MapReduce)
{
failComments.Add("Cannot merge map/reduce indexes");
}
if (indexData.Index.Maps.Count > 1)
{
failComments.Add("Cannot merge multi map indexes");
}
if (indexData.NumberOfFromClauses > 1)
{
failComments.Add("Cannot merge indexes that have more than a single from clause");
}
if (indexData.NumberOfSelectClauses > 1)
{
failComments.Add("Cannot merge indexes that have more than a single select clause");
}
if (indexData.HasWhere)
{
failComments.Add("Cannot merge indexes that have a where clause");
}
if (indexData.HasGroup)
{
failComments.Add("Cannot merge indexes that have a group by clause");
}
if (indexData.HasLet)
{
failComments.Add("Cannot merge indexes that are using a let clause");
}
if (indexData.HasOrder)
{
failComments.Add("Cannot merge indexes that have an order by clause");
}
return(failComments);
}
private static bool AreSelectClausesTheSame(IndexData index, Dictionary <string, ExpressionSyntax> selectExpressionDict)
{
if (index.SelectExpressions.Count != selectExpressionDict.Count)
{
return(false);
}
foreach (var pair in index.SelectExpressions)
{
if (selectExpressionDict.TryGetValue(pair.Key, out ExpressionSyntax expressionValue) == false)
{
return(false);
}
// for the same key, they have to be the same
var ySelectExpr = ExtractValueFromExpression(expressionValue);
var xSelectExpr = ExtractValueFromExpression(pair.Value);
if (xSelectExpr != ySelectExpr)
{
return(false);
}
}
return(true);
}
public IndexVisitor(IndexData indexData)
{
_indexData = indexData;
indexData.NumberOfFromClauses = 0;
indexData.SelectExpressions = new Dictionary <string, ExpressionSyntax>();
}
private bool CompareIndexFieldOptions(IndexData index1Data, IndexData index2Data)
{
var intersectNames = index2Data.SelectExpressions.Keys.Intersect(index1Data.SelectExpressions.Keys).ToArray();
return(DataDictionaryCompare(index1Data.Index.Fields, index2Data.Index.Fields, intersectNames));
}