public UpdateObject(string collection, Updator updator,
ITreePredicate filterPredicate)
{
_collection = collection;
_updator = updator;
_filterPredicate = filterPredicate;
}
public ITreePredicate Expand()
{
foreach (var predciate in _predciates)
{
var orPredicate = predciate as OrTreePredicate;
if (orPredicate != null)
{
ITreePredicate orParent = null;
foreach (var childPredciate in orPredicate.TreePredicates)
{
orParent = orParent ?? new OrTreePredicate();
if (orPredicate.TreePredicates.Count > 1)
{
var andChild = new AndTreePredicate();
foreach (var sibling in _predciates)
{
if (sibling != orPredicate)
{
andChild.Add(sibling);
}
}
andChild.Add(childPredciate);
((OrTreePredicate)orParent).Add(andChild);
}
else
{
orParent = childPredciate;
}
}
return(orParent);
}
}
foreach (var predciate in _predciates)
{
var resultPred = predciate.Expand();
if (resultPred != null)
{
ITreePredicate returnPredciate = new AndTreePredicate();
foreach (var sibling in _predciates)
{
if (sibling != predciate)
{
((AndTreePredicate)returnPredciate).Add((ITreePredicate)sibling.Clone());
}
}
((AndTreePredicate)returnPredciate).Add(resultPred);
return(returnPredciate);
}
}
return(null);
}
public SelectObject(bool isdistinct, List <IEvaluable> projections,
string collection, ITreePredicate filterPredicate, List <IEvaluable> groupValue,
List <IEvaluable> orderValue, IntegerConstantValue skip, IntegerConstantValue limit, string hint)
{
_isdistinct = isdistinct;
_projections = projections;
_collection = collection;
_filterPredicate = filterPredicate;
_groupValue = groupValue;
_orderValue = orderValue;
_skip = skip;
_limit = limit;
_hint = hint;
}
public ITreePredicate Contract()
{
Dictionary <int, ITreePredicate> contractedPreds = new Dictionary <int, ITreePredicate>();
for (int i = 0; i < _predciates.Count; i++)
{
ITreePredicate contractedPred = _predciates[i].Contract();
if (contractedPred != null)
{
while (contractedPred.Contract() != null)
{
contractedPred = contractedPred.Contract();
}
contractedPreds[i] = contractedPred;
}
}
if (contractedPreds.Count.Equals(0))
{
return(null);
}
AndTreePredicate returnAnd = new AndTreePredicate();
for (int i = 0; i < _predciates.Count; i++)
{
if (contractedPreds.ContainsKey(i))
{
returnAnd.Add(contractedPreds[i]);
}
else
{
returnAnd.Add(_predciates[i]);
}
}
ITreePredicate contractedExpr = returnAnd;
while (contractedExpr.Contract() != null)
{
contractedExpr = contractedExpr.Contract();
}
return(contractedExpr);
}
/// <summary>
/// Tries to assign compound indexes to expressions if applicable...
/// </summary>
private static List <ProxyAndPredicate> AssignCompoundIndices(ProxyAndPredicate set,
IEnumerable <IIndex> indexes, IQueryStore queryStore)
{
var attribExprList = new OrderedList <string, ComparisonPredicate>();
var proxyPredicates = new List <ProxyAndPredicate>();
//For every expression in the set ready for assignment.
foreach (var expresson in set.TreePredicates)
{
var expression = (ComparisonPredicate)expresson;
if (expression.IsBinaryExpression)
{
continue;
}
attribExprList.Add(expression.AttributeNames[0], expression);
}
//Each compound index will create a new state of the expression.
foreach (var index in indexes)
{
int matchedNumber = 0;
var matchedAttribs = new List <string>();
//If keys (attributes list) does not contain the first prefix of the index
//Then the index is not usable.
if (attribExprList.ContainsKey(index.Attributes.Name))
{
matchedAttribs.Add(index.Attributes.Name);
matchedNumber += attribExprList[index.Attributes.Name].Count;
}
//if matched attributes are < 2 no need of compound assignment.
if (matchedAttribs.Count < 2)
{
continue;
}
//Assign each of them an index and get them to the predicate, and get the one with the lowest cost.
ComparisonPredicate cheapestExpression = attribExprList[matchedAttribs[0]][0];
IPredicate cheapestPredicate = cheapestExpression.AssignIndexPredicate(index, queryStore);
for (int i = 1; i < attribExprList[matchedAttribs[0]].Count; i++)
{
ComparisonPredicate tempExpression = attribExprList[matchedAttribs[0]][i];
IPredicate tempPredicate = tempExpression.AssignIndexPredicate(index, queryStore);
if (tempPredicate.Statistics[Statistic.ExpectedIO] <
cheapestPredicate.Statistics[Statistic.ExpectedIO])
{
cheapestExpression = tempExpression;
cheapestPredicate = tempPredicate;
}
}
//For filteration and adding rest of expressions to the index.
ITreePredicate assingedExpression = null;
if (!matchedNumber.Equals(2))
{
AndTreePredicate assingedAnd = new AndTreePredicate();
foreach (var attribute in matchedAttribs)
{
foreach (var expression in attribExprList[attribute])
{
if (expression != cheapestExpression)
{
assingedAnd.Add(expression);
}
}
}
assingedExpression = assingedAnd;
}
else
{
foreach (var expression in attribExprList[matchedAttribs[1]])
{
assingedExpression = expression;
}
}
FilterPredicate filterPredicate = new FilterPredicate(assingedExpression, index);
filterPredicate.AddChildPredicate(cheapestPredicate);
ProxyAndPredicate proxyAnd = (ProxyAndPredicate)set.Clone();
//Removing assigned expressions.
foreach (var attribute in matchedAttribs)
{
foreach (var expression in attribExprList[attribute])
{
proxyAnd.TreePredicates.Remove(expression);
}
}
proxyAnd.AddChildPredicate(new ProxyPredicate(filterPredicate, null));
proxyPredicates.Add(proxyAnd);
}
foreach (var proxyAnd in proxyPredicates)
{
//Recursive call for each ProxyAndPredicate.
if (proxyAnd.TreePredicates.Count > 1)
{
var values = AssignCompoundIndices(proxyAnd, indexes, queryStore);
foreach (var value in values)
{
proxyPredicates.Add(value);
}
}
}
return(proxyPredicates);
}
public void Add(ITreePredicate item)
{
_predciates.Add(item);
}
public void AddExpression(ITreePredicate expression)
{
_treePredicates.Add(expression);
}
public ITreePredicate Contract()
{
if (!IsTerminal)
{
Dictionary <int, ITreePredicate> contractedPreds = new Dictionary <int, ITreePredicate>();
for (int i = 0; i < _predciates.Count; i++)
{
ITreePredicate contracted = _predciates[i].Contract();
if (contracted != null)
{
while (contracted.Contract() != null)
{
contracted = contracted.Contract();
}
contractedPreds[i] = contracted;
}
}
if (contractedPreds.Count.Equals(0))
{
return(null);
}
OrTreePredicate returnOr = new OrTreePredicate();
for (int i = 0; i < _predciates.Count; i++)
{
if (contractedPreds.ContainsKey(i))
{
returnOr.Add(contractedPreds[i]);
}
else
{
returnOr.Add(_predciates[i]);
}
}
ITreePredicate contractedPred = returnOr;
while (contractedPred.Contract() != null)
{
contractedPred = contractedPred.Contract();
}
return(contractedPred);
}
List <AndTreePredicate> ands = new List <AndTreePredicate>();
foreach (var predciate in _predciates)
{
if (!(predciate is AndTreePredicate))
{
return(null);
}
ands.Add((AndTreePredicate)(predciate));
}
if (ands.Count < 2)
{
return(null);
}
ITreePredicate commonPred = null;
foreach (var expression in ands[0].TreePredicates)
{
commonPred = expression;
for (int i = 1; i < ands.Count; i++)
{
if (ands[i].TreePredicates.Count < 2 ||
!ands[i].TreePredicates.Contains(expression))
{
return(null);
}
}
}
AndTreePredicate returnPred = new AndTreePredicate();
returnPred.Add(commonPred);
OrTreePredicate orChild = new OrTreePredicate();
foreach (var and in ands)
{
foreach (var predciate in and.TreePredicates)
{
if (!predciate.Equals(commonPred))
{
orChild.Add(predciate);
}
}
}
returnPred.Add(orChild);
ITreePredicate contractPred = returnPred;
while (contractPred.Contract() != null)
{
contractPred = contractPred.Contract();
}
return(contractPred);
}
public void AddTreePredicate(ITreePredicate predciate)
{
_treePredicates.Add(predciate);
}
public DeleteObject(string collection, ITreePredicate filterPredicate = null)
{
_collection = collection;
_fliterPredicate = filterPredicate;
}
public QueryPlan GetQueryPlan(IDmObject parsedQuery, IQuery query, IQueryStore queryStore, MetadataIndex rowsEnumerator)
{
//Todo: Plan's cache's key decision (query-string based plan cache/optimizable-section based cache).
OrderedList <double, IProxyPredicate> sortedPlans = new OrderedList <double, IProxyPredicate>();
var optimizableQuery = parsedQuery as IFilterObject;
var criteria = AddQueryCriteria(parsedQuery, query.Parameters, queryStore);
var queryPlan = new QueryPlan {
Criteria = criteria
};
if (optimizableQuery != null && optimizableQuery.WherePredicate != null)
{
ITreePredicate whereExpression = optimizableQuery.WherePredicate;
ITreePredicate contractedExpression = whereExpression.Contract();
if (contractedExpression == null)
{
contractedExpression = whereExpression;
}
List <ITreePredicate> distribCombinations = new List <ITreePredicate>();
distribCombinations.Add(contractedExpression);
//Todo: Restrict this call if there doesn't exist a compound index.
while (contractedExpression.Expand() != null)
{
distribCombinations.Add(contractedExpression.Expand());
contractedExpression = contractedExpression.Expand();
}
foreach (var treePredicate in distribCombinations)
{
if (treePredicate is OrTreePredicate || treePredicate is AndTreePredicate)
{
break;
}
if (treePredicate is ComparisonPredicate)
{
DocumentKey documentKey = null;
if (((ComparisonPredicate)treePredicate).TryGetProxyKeyPredicate(rowsEnumerator, out documentKey))
{
IProxyPredicate optimizablePredicate = new ProxyPredicate(new KeyPredicate(documentKey, rowsEnumerator), treePredicate);
sortedPlans.Add(optimizablePredicate.Statistics[Statistic.ExpectedIO], optimizablePredicate);
queryPlan.Predicate = sortedPlans.FirstValues[0].GetExecutionPredicate(queryStore);
return(queryPlan);
}
}
}
foreach (var expressionState in distribCombinations)
{
IProxyPredicate optimizablePredicate = expressionState.GetProxyExecutionPredicate(_indexManager, queryStore, rowsEnumerator);
sortedPlans.Add(optimizablePredicate.Statistics[Statistic.ExpectedIO], optimizablePredicate);
//Todo: Add optimizedPredicate to the SortedList by the cost.
}
queryPlan.Predicate = sortedPlans.FirstValues[0].GetExecutionPredicate(queryStore);
}
else
{
if (criteria.GroupFields != null && criteria.GroupFields.Count == 1 && criteria.GroupFields[0] is AllField && criteria.ContainsAggregations)
{
if (criteria.Aggregations.Count == 1 && criteria.Aggregations[0].Aggregation is COUNT &&
criteria.Aggregations[0].Evaluation is AllEvaluable)
{
queryPlan.Criteria.GroupByField = null;
queryPlan.Predicate = new SpecialCountPredicate(rowsEnumerator.KeyCount);
queryPlan.IsSpecialExecution = true;
return(queryPlan);
}
}
//Todo:1 Projection variable-based index assigning (Functions' arguments + attributes).
queryPlan.Predicate = GetSelectAllPredicate(criteria, rowsEnumerator);
}
return(queryPlan);
}
public ProxyPredicate(IPredicate predicate, ITreePredicate expression)
{
_predicate = predicate;
_expression = expression;
}
public FilterPredicate(ITreePredicate condition, IIndex sourceIndex)
{
_condition = condition;
source = sourceIndex;
}