public override IQueryState Visit(JoinQueryExpression exp)
{
ResultElement resultElement = new ResultElement();
IQueryState qs = QueryExpressionVisitor.VisitQueryExpression(exp.PrevExpression);
FromQueryResult fromQueryResult = qs.ToFromQueryResult();
DbFromTableExpression fromTable = fromQueryResult.FromTable;
resultElement.FromTable = fromTable;
List <IMappingObjectExpression> moeList = new List <IMappingObjectExpression>();
moeList.Add(fromQueryResult.MappingObjectExpression);
foreach (JoiningQueryInfo joiningQueryInfo in exp.JoinedQueries)
{
JoinQueryResult joinQueryResult = JoinQueryExpressionVisitor.VisitQueryExpression(joiningQueryInfo.Query.QueryExpression, resultElement, joiningQueryInfo.JoinType, joiningQueryInfo.Condition, moeList);
var nullChecking = DbExpression.CaseWhen(new DbCaseWhenExpression.WhenThenExpressionPair(joinQueryResult.JoinTable.Condition, DbConstantExpression.One), DbConstantExpression.Null, DbConstantExpression.One.Type);
if (joiningQueryInfo.JoinType == JoinType.LeftJoin)
{
joinQueryResult.MappingObjectExpression.SetNullChecking(nullChecking);
}
else if (joiningQueryInfo.JoinType == JoinType.RightJoin)
{
foreach (IMappingObjectExpression item in moeList)
{
item.SetNullChecking(nullChecking);
}
}
else if (joiningQueryInfo.JoinType == JoinType.FullJoin)
{
joinQueryResult.MappingObjectExpression.SetNullChecking(nullChecking);
foreach (IMappingObjectExpression item in moeList)
{
item.SetNullChecking(nullChecking);
}
}
fromTable.JoinTables.Add(joinQueryResult.JoinTable);
moeList.Add(joinQueryResult.MappingObjectExpression);
}
IMappingObjectExpression moe = SelectorExpressionVisitor.ResolveSelectorExpression(exp.Selector, moeList);
resultElement.MappingObjectExpression = moe;
GeneralQueryState queryState = new GeneralQueryState(resultElement);
return(queryState);
}
DbSqlQueryExpression ConvertToDbSqlQueryExpression(Expression exp, Type resultType)
{
if (!IsIQueryType(exp.Type))
{
throw new NotSupportedException(exp.ToString());
}
QueryBase query = ExpressionEvaluator.Evaluate(exp) as QueryBase;
IQueryState qs = QueryExpressionVisitor.VisitQueryExpression(query.QueryExpression, this._scopeParameters, this._scopeTables);
MappingData mappingData = qs.GenerateMappingData();
DbSqlQueryExpression sqlQueryExpression = mappingData.SqlQuery.Update(resultType);
return(sqlQueryExpression);
}
public override IQueryState Visit(JoinQueryExpression exp)
{
IQueryState qs = QueryExpressionVisitor.VisitQueryExpression(exp.PrevExpression, this._scopeParameters, this._scopeTables);
ResultElement resultElement = qs.ToFromQueryResult();
List <IMappingObjectExpression> moeList = new List <IMappingObjectExpression>();
moeList.Add(resultElement.MappingObjectExpression);
foreach (JoiningQueryInfo joiningQueryInfo in exp.JoinedQueries)
{
ScopeParameterDictionary scopeParameters = resultElement.ScopeParameters.Clone(resultElement.ScopeParameters.Count + moeList.Count);
for (int i = 0; i < moeList.Count; i++)
{
ParameterExpression p = joiningQueryInfo.Condition.Parameters[i];
scopeParameters[p] = moeList[i];
}
JoinQueryResult joinQueryResult = JoinQueryExpressionVisitor.VisitQueryExpression(joiningQueryInfo.Query.QueryExpression, resultElement, joiningQueryInfo.JoinType, joiningQueryInfo.Condition, scopeParameters);
var nullChecking = DbExpression.CaseWhen(new DbCaseWhenExpression.WhenThenExpressionPair(joinQueryResult.JoinTable.Condition, DbConstantExpression.One), DbConstantExpression.Null, DbConstantExpression.One.Type);
if (joiningQueryInfo.JoinType == JoinType.LeftJoin)
{
joinQueryResult.MappingObjectExpression.SetNullChecking(nullChecking);
}
else if (joiningQueryInfo.JoinType == JoinType.RightJoin)
{
foreach (IMappingObjectExpression item in moeList)
{
item.SetNullChecking(nullChecking);
}
}
else if (joiningQueryInfo.JoinType == JoinType.FullJoin)
{
joinQueryResult.MappingObjectExpression.SetNullChecking(nullChecking);
foreach (IMappingObjectExpression item in moeList)
{
item.SetNullChecking(nullChecking);
}
}
resultElement.FromTable.JoinTables.Add(joinQueryResult.JoinTable);
moeList.Add(joinQueryResult.MappingObjectExpression);
}
ScopeParameterDictionary scopeParameters1 = resultElement.ScopeParameters.Clone(resultElement.ScopeParameters.Count + moeList.Count);
for (int i = 0; i < moeList.Count; i++)
{
ParameterExpression p = exp.Selector.Parameters[i];
scopeParameters1[p] = moeList[i];
}
IMappingObjectExpression moe = SelectorExpressionVisitor.ResolveSelectorExpression(exp.Selector, scopeParameters1, resultElement.ScopeTables);
resultElement.MappingObjectExpression = moe;
GeneralQueryState queryState = new GeneralQueryState(resultElement);
return(queryState);
}
public static IQueryState VisitQueryExpression(QueryExpression queryExpression, ScopeParameterDictionary scopeParameters, KeyDictionary <string> scopeTables)
{
QueryExpressionVisitor reducer = new QueryExpressionVisitor(scopeParameters, scopeTables);
return(queryExpression.Accept(reducer));
}
