update

表达式函数.md

@@ -22,7 +22,7 @@ if (xxx)
 ## In查询
 
 ```csharp
-var t1 = fsql.Select<T>()
+fsql.Select<T>()
   .Where(a => new[] { 1, 2, 3 }.Contains(a.Id))
   .ToList();
 //SELECT .. FROM ..
@@ -58,40 +58,38 @@ var t2 = fsql.Select<T>()
 ## In子表
 
 ```csharp
-var list2 = fsql.Select<T>()
-  .Where(a => fsql.Select<T>()
-      .ToList(b => b.Id)
-      .Contains(a.Id))
+fsql.Select<Topic>()
+  .Where(a => fsql.Select<Topic>().As("b").ToList(b => b.Id).Contains(a.Id))
   .ToList();
-// SELECT a.`Id`, a.`Clicks`, a.`TypeGuid`, a.`Title`, a.`CreateTime` 
-// FROM `tb_topic` a 
-// WHERE (((cast(a.`Id` as char)) in (SELECT b.`Title` 
-//   FROM `tb_topic` b)))
+//SELECT a.`Id`, a.`Title`, a.`Clicks`, a.`CreateTime`, a.`CategoryId`
+//FROM `Topic` a
+//WHERE (((a.`Id`) in (SELECT b.`Id`
+//    FROM `Topic` b)))
 ```
 
 ## Exists子表
 
 ```csharp
-var list2 = fsql.Select<T>()
-  .Where(a => fsql.Select<T>()
-    .Any(b => b.Id == a.Id))
+fsql.Select<Topic>()
+  .Where(a => fsql.Select<Topic>().As("b").Where(b => b.Id == a.Id).Any())
   .ToList();
-// SELECT a.`Id`, a.`TypeGuid`, a.`Title`, a.`CreateTime` 
-// FROM `xxx` a 
-// WHERE (exists(SELECT 1 
-// FROM `xxx` b 
-// WHERE (b.`Id` = a.`Id`)))
+//SELECT a.`Id`, a.`Title`, a.`Clicks`, a.`CreateTime`, a.`CategoryId`
+//FROM `Topic` a
+//WHERE (exists(SELECT 1
+//    FROM `Topic` b
+//    WHERE (b.`Id` = a.`Id`)
+//    limit 0,1))
 ```
 
 ## 查找今天创建的数据
 
 ```csharp
-var t3 = fsql.Select<T>()
+fsql.Select<T>()
   .Where(a => a.CreateTime.Date == DateTime.Today)
   .ToList();
 //这行代码说明 FreeSql 表达式解析强大，不是所有 ORM 都支持
 
-var t4 = fsql.Select<T>()
+fsql.Select<T>()
   .Where(a => a.CreateTime.Between(DateTime.Today, DateTime.Today.AddDays(1)))
   .ToList();
 //正常用法应该是这样
@@ -102,7 +100,7 @@ var t4 = fsql.Select<T>()
 ## 日期格式化
 
 ```csharp
-var t4 = fsql.Select<T>()
+fsql.Select<T>()
   .First(a => a.CreateTime.ToString("HH:mm:ss");
 // SELECT date_format(a.`CreateTime`, '%H:%i:%s') as1 
 // FROM `xxx` a 
@@ -128,6 +126,30 @@ fsql.Select<T1, T2>()
 
 > v1.6.0 利用自定义解析功能，增加 SqlExt.Rank().Over().PartitionBy(...)、MySql group_concat 常用函数，欢迎 PR 补充
 
+## 返回子查询字段
+
+```csharp
+List<匿名类> t10 = fsql.Select<Topic>().ToList(a => new {
+    a.Id,
+    count = fsql.Select<T2>().Count(),
+    max = fsql.Select<T2>().Max(b => b.Id),
+    min = fsql.Select<T2>().Min(b => b.Id),
+    name = fsql.Select<2>().First(b => b.name)
+});
+```
+
+## 返回子查询集合
+
+> v3.2.650+ 以下最多执行3次 SQL
+
+```csharp
+List<匿名类> t11 = fsql.Select<Topic>().ToList(a => new {
+    a.Id,
+    list1 = fsql.Select<T2>().ToList(),
+    list2 = fsql.Select<T2>().Where(b => b.TopicId == a.Id).ToList()
+});
+```
+
 ## 自定义解析
 
 ```csharp

返回数据.md

@@ -61,7 +61,7 @@ List<匿名类> t10 = fsql.Select<Topic>().ToList(a => new {
     name = fsql.Select<2>().First(b => b.name)
 });
 
-//返回子查询集合 v3.2.650+
+//返回子查询集合 v3.2.650+ 以下最多执行3次 SQL
 List<匿名类> t11 = fsql.Select<Topic>().ToList(a => new {
     a.Id,
     list1 = fsql.Select<T2>().ToList(),