/// <summary>
/// 创建关联一个强类型查询
/// </summary>
/// <typeparam name="TJoinResult"></typeparam>
/// <param name="resultSelect"></param>
/// <param name="expression"></param>
/// <param name="joinType"></param>
/// <returns></returns>
public ILambdaQueryViewJoin <T, TJoinResult> Join <TJoinResult>(ILambdaQueryResultSelect <TJoinResult> resultSelect, Expression <Func <T, TJoinResult, bool> > expression, JoinType joinType = JoinType.Inner)
{
if (!resultSelect.BaseQuery.__FromDbContext)
{
throw new Exception("关联需要由LambdaQuery.CreateQuery创建");
}
var query2 = new LambdaQueryViewJoin <T, TJoinResult>(this, resultSelect);
//var innerType = typeof(TSource);
var innerType = resultSelect.InnerType;
//var prefix1 = GetPrefix(innerType);
var prefix2 = GetPrefix(typeof(TJoinResult));
var typeQuery = new TypeQuery(innerType, prefix2);
var baseQuery = resultSelect.BaseQuery;
QueryParames.AddRange(baseQuery.QueryParames);
string innerQuery = baseQuery.GetQuery();
typeQuery.InnerQuery = innerQuery;
string condition = FormatJoinExpression(expression.Body);
AddInnerRelation(typeQuery, joinType, condition);
return(query2);
}
/// <summary>
/// 联合查询
/// 会清除父查询的排序
/// </summary>
/// <typeparam name="TResult2"></typeparam>
/// <param name="resultSelect"></param>
/// <param name="unionType"></param>
/// <returns></returns>
public ILambdaQueryResultSelect <TResult> Union <TResult2>(ILambdaQueryResultSelect <TResult2> resultSelect, UnionType unionType = UnionType.UnionAll)
{
BaseQuery.CleanOrder();//清除OrderBy
BaseQuery.AddUnion(resultSelect.BaseQuery, unionType);
return(this);
}
/// <summary>
/// 关联查询分支
/// </summary>
/// <param name="query"></param>
/// <param name="_resultSelect"></param>
internal LambdaQueryViewJoin(LambdaQuery <T> query, ILambdaQueryResultSelect <TJoinResult> _resultSelect)
{
BaseQuery = query;
resultSelect = _resultSelect;
}
ILambdaQuery <T> InnerSelect <TResult>(Expression <Func <T, TResult> > outField, ILambdaQueryResultSelect <TResult> query, string type, string innerJoinSql = "")
{
if (!query.BaseQuery.__FromDbContext)
{
throw new Exception("关联需要由LambdaQuery.CreateQuery创建");
}
var baseQuery = query.BaseQuery;
QueryParames.AddRange(baseQuery.QueryParames);
//foreach (var kv in baseQuery.QueryParames)
//{
// QueryParames[kv.Key] = kv.Value;
//}
var query2 = baseQuery.GetQuery();
return(InnerSelect(outField, query2, type));
}
/// <summary>
/// 按!=
/// 等效为table.field !=(select field from table2)
/// </summary>
/// <typeparam name="TResult"></typeparam>
/// <param name="query"></param>
/// <param name="outField"></param>
/// <returns></returns>
public ILambdaQuery <T> NotEqual <TResult>(ILambdaQueryResultSelect <TResult> query, Expression <Func <T, TResult> > outField)
{
return(InnerSelect(outField, query, "!="));
}
/// <summary>
/// 按查询not exists
/// 等效为 not exixts(select field from table2)
/// </summary>
/// <typeparam name="TResult"></typeparam>
/// <param name="query"></param>
/// <returns></returns>
public ILambdaQuery <T> NotExists <TResult>(ILambdaQueryResultSelect <TResult> query)
{
return(InnerSelect(null, query, "not exists"));
}
