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 == DbJoinType.LeftJoin)
{
joinQueryResult.MappingObjectExpression.SetNullChecking(nullChecking);
}
else if (joiningQueryInfo.JoinType == DbJoinType.RightJoin)
{
foreach (IMappingObjectExpression item in moeList)
{
item.SetNullChecking(nullChecking);
}
}
else if (joiningQueryInfo.JoinType == DbJoinType.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.VisitSelectExpression(exp.Selector, moeList);
resultElement.MappingObjectExpression = moe;
GeneralQueryState queryState = new GeneralQueryState(resultElement);
return(queryState);
}
public virtual GeneralQueryState AsSubQueryState()
{
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
QueryModel newQueryModel = new QueryModel(this._queryModel.ScopeParameters, this._queryModel.ScopeTables, this._queryModel.IgnoreFilters);
DbTableSegment tableSeg = new DbTableSegment(subQuery, newQueryModel.GenerateUniqueTableAlias(), LockType.Unspecified);
DbFromTableExpression fromTable = new DbFromTableExpression(tableSeg);
newQueryModel.FromTable = fromTable;
DbTable aliasTable = new DbTable(tableSeg.Alias);
//TODO 根据旧的生成新 ResultModel
IObjectModel newResultModel = this.QueryModel.ResultModel.ToNewObjectModel(sqlQuery, aliasTable, fromTable);
newQueryModel.ResultModel = newResultModel;
//得将 subQuery.SqlQuery.Orders 告诉 以下创建的 result
//将 orderPart 传递下去
for (int i = 0; i < this.QueryModel.Orderings.Count; i++)
{
DbOrdering ordering = this.QueryModel.Orderings[i];
DbExpression orderingExp = ordering.Expression;
string alias = null;
DbColumnSegment columnExpression = sqlQuery.ColumnSegments.Find(a => DbExpressionEqualityComparer.EqualsCompare(orderingExp, a.Body));
// 对于重复的则不需要往 sqlQuery.Columns 重复添加了
if (columnExpression != null)
{
alias = columnExpression.Alias;
}
else
{
alias = Utils.GenerateUniqueColumnAlias(sqlQuery);
DbColumnSegment columnSeg = new DbColumnSegment(orderingExp, alias);
sqlQuery.ColumnSegments.Add(columnSeg);
}
DbColumnAccessExpression columnAccessExpression = new DbColumnAccessExpression(aliasTable, DbColumn.MakeColumn(orderingExp, alias));
newQueryModel.Orderings.Add(new DbOrdering(columnAccessExpression, ordering.OrderType));
}
newQueryModel.InheritOrderings = true;
GeneralQueryState queryState = new GeneralQueryState(newQueryModel);
return(queryState);
}
static DbSqlQueryExpression WrapSqlQuery(DbSqlQueryExpression sqlQuery, DbTable table, List <DbColumnSegment> columnSegments = null)
{
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
DbSqlQueryExpression newSqlQuery = new DbSqlQueryExpression();
DbTableSegment tableSeg = new DbTableSegment(subQuery, table.Name, LockType.Unspecified);
DbFromTableExpression fromTableExp = new DbFromTableExpression(tableSeg);
newSqlQuery.Table = fromTableExp;
CopyColumnSegments(columnSegments ?? subQuery.SqlQuery.ColumnSegments, newSqlQuery.ColumnSegments, table);
return(newSqlQuery);
}
public string GenerateUniqueTableAlias(string prefix = UtilConstants.DefaultTableAlias)
{
string alias = prefix;
int i = 0;
DbFromTableExpression fromTable = this.FromTable;
while (this.ScopeTables.ContainsKey(alias) || ExistTableAlias(fromTable, alias))
{
alias = prefix + i.ToString();
i++;
}
this.ScopeTables[alias] = alias;
return(alias);
}
static bool ExistTableAlias(DbFromTableExpression fromTable, string alias)
{
if (string.Equals(fromTable.Table.Alias, alias, StringComparison.OrdinalIgnoreCase))
{
return(true);
}
foreach (var item in fromTable.JoinTables)
{
if (ExistTableAlias(item, alias))
{
return(true);
}
}
return(false);
}
public virtual FromQueryResult ToFromQueryResult()
{
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
DbTableSegment tableSeg = new DbTableSegment(subQuery, UtilConstants.DefaultTableAlias);
DbFromTableExpression fromTable = new DbFromTableExpression(tableSeg);
DbTable table = new DbTable(tableSeg.Alias);
IMappingObjectExpression newMoe = this.Result.MappingObjectExpression.ToNewObjectExpression(sqlQuery, table);
FromQueryResult result = new FromQueryResult();
result.FromTable = fromTable;
result.MappingObjectExpression = newMoe;
return(result);
}
public virtual ResultElement ToFromQueryResult()
{
ResultElement result = new ResultElement(this._resultElement.ScopeParameters, this._resultElement.ScopeTables);
string alias = result.GenerateUniqueTableAlias(UtilConstants.DefaultTableAlias);
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
DbTableSegment tableSeg = new DbTableSegment(subQuery, alias, LockType.Unspecified);
DbFromTableExpression fromTable = new DbFromTableExpression(tableSeg);
DbTable table = new DbTable(tableSeg.Alias);
IMappingObjectExpression newMoe = this.Result.MappingObjectExpression.ToNewObjectExpression(sqlQuery, table);
result.FromTable = fromTable;
result.MappingObjectExpression = newMoe;
return(result);
}
public virtual QueryModel ToFromQueryModel()
{
QueryModel queryModel = new QueryModel(this._queryModel.ScopeParameters, this._queryModel.ScopeTables, this._queryModel.IgnoreFilters);
string alias = queryModel.GenerateUniqueTableAlias(UtilConstants.DefaultTableAlias);
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
DbTableSegment tableSeg = new DbTableSegment(subQuery, alias, LockType.Unspecified);
DbFromTableExpression fromTable = new DbFromTableExpression(tableSeg);
DbTable aliasTable = new DbTable(tableSeg.Alias);
IObjectModel newModel = this.QueryModel.ResultModel.ToNewObjectModel(sqlQuery, aliasTable, fromTable);
queryModel.FromTable = fromTable;
queryModel.ResultModel = newModel;
return(queryModel);
}
public string GenerateUniqueTableAlias(string prefix = UtilConstants.DefaultTableAlias)
{
if (this.FromTable == null)
{
return(prefix);
}
string alias = prefix;
int i = 0;
DbFromTableExpression fromTable = this.FromTable;
while (ExistTableAlias(fromTable, alias))
{
alias = prefix + i.ToString();
i++;
}
return(alias);
}
public virtual JoinQueryResult ToJoinQueryResult(DbJoinType joinType, LambdaExpression conditionExpression, DbFromTableExpression fromTable, List <IMappingObjectExpression> moeList, string tableAlias)
{
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
string alias = tableAlias;
DbTableSegment tableSeg = new DbTableSegment(subQuery, alias);
DbTable table = new DbTable(tableSeg.Alias);
IMappingObjectExpression newMoe = this.Result.MappingObjectExpression.ToNewObjectExpression(sqlQuery, table);
List <IMappingObjectExpression> moes = new List <IMappingObjectExpression>(moeList.Count + 1);
moes.AddRange(moeList);
moes.Add(newMoe);
DbExpression condition = GeneralExpressionVisitor.ParseLambda(conditionExpression, moes);
DbJoinTableExpression joinTable = new DbJoinTableExpression(joinType, tableSeg, condition);
JoinQueryResult result = new JoinQueryResult();
result.MappingObjectExpression = newMoe;
result.JoinTable = joinTable;
return(result);
}
public override DbExpression Visit(DbFromTableExpression exp)
{
return(exp);
}
public override DbExpression Visit(DbFromTableExpression exp)
{
return(exp.Accept(this._generator));
}
public abstract T Visit(DbFromTableExpression exp);
public virtual JoinQueryResult ToJoinQueryResult(JoinType joinType, LambdaExpression conditionExpression, DbFromTableExpression fromTable, List<IMappingObjectExpression> moeList, string tableAlias)
{
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
string alias = tableAlias;
DbTableSegment tableSeg = new DbTableSegment(subQuery, alias);
DbTable table = new DbTable(tableSeg.Alias);
IMappingObjectExpression newMoe = this.Result.MappingObjectExpression.ToNewObjectExpression(sqlQuery, table);
List<IMappingObjectExpression> moes = new List<IMappingObjectExpression>(moeList.Count + 1);
moes.AddRange(moeList);
moes.Add(newMoe);
DbExpression condition = GeneralExpressionVisitor.VisitPredicate(conditionExpression, moes);
DbJoinTableExpression joinTable = new DbJoinTableExpression(joinType, tableSeg, condition);
JoinQueryResult result = new JoinQueryResult();
result.MappingObjectExpression = newMoe;
result.JoinTable = joinTable;
return result;
}
public virtual FromQueryResult ToFromQueryResult()
{
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
DbTableSegment tableSeg = new DbTableSegment(subQuery, ResultElement.DefaultTableAlias);
DbFromTableExpression fromTable = new DbFromTableExpression(tableSeg);
DbTable table = new DbTable(tableSeg.Alias);
IMappingObjectExpression newMoe = this.Result.MappingObjectExpression.ToNewObjectExpression(sqlQuery, table);
FromQueryResult result = new FromQueryResult();
result.FromTable = fromTable;
result.MappingObjectExpression = newMoe;
return result;
}
public virtual GeneralQueryState AsSubQueryState()
{
DbSqlQueryExpression sqlQuery = this.CreateSqlQuery();
DbSubQueryExpression subQuery = new DbSubQueryExpression(sqlQuery);
ResultElement result = new ResultElement();
DbTableSegment tableSeg = new DbTableSegment(subQuery, result.GenerateUniqueTableAlias());
DbFromTableExpression fromTable = new DbFromTableExpression(tableSeg);
result.FromTable = fromTable;
DbTable table = new DbTable(tableSeg.Alias);
//TODO 根据旧的生成新 MappingMembers
IMappingObjectExpression newMoe = this.Result.MappingObjectExpression.ToNewObjectExpression(sqlQuery, table);
result.MappingObjectExpression = newMoe;
//得将 subQuery.SqlQuery.Orders 告诉 以下创建的 result
//将 orderPart 传递下去
if (this.Result.OrderSegments.Count > 0)
{
for (int i = 0; i < this.Result.OrderSegments.Count; i++)
{
DbOrderSegment orderPart = this.Result.OrderSegments[i];
DbExpression orderExp = orderPart.DbExpression;
string alias = null;
DbColumnSegment columnExpression = sqlQuery.ColumnSegments.Where(a => DbExpressionEqualityComparer.EqualsCompare(orderExp, a.Body)).FirstOrDefault();
// 对于重复的则不需要往 sqlQuery.Columns 重复添加了
if (columnExpression != null)
{
alias = columnExpression.Alias;
}
else
{
alias = Utils.GenerateUniqueColumnAlias(sqlQuery);
DbColumnSegment columnSeg = new DbColumnSegment(orderExp, alias);
sqlQuery.ColumnSegments.Add(columnSeg);
}
DbColumnAccessExpression columnAccessExpression = new DbColumnAccessExpression(orderExp.Type, table, alias);
result.OrderSegments.Add(new DbOrderSegment(columnAccessExpression, orderPart.OrderType));
}
}
result.IsOrderSegmentsFromSubQuery = true;
GeneralQueryState queryState = new GeneralQueryState(result);
return queryState;
}
