From d2c0609cccb110a80d01e5185fdccfd4c09f2592 Mon Sep 17 00:00:00 2001
From: 2881099 <2881099@users.noreply.github.com>
Date: Fri, 12 Dec 2025 21:33:08 +0800
Subject: [PATCH] Updated Query from Multi Tables (markdown)

---
 Query-from-Multi-Tables.md | 54 ++++++++++----------------------------
 1 file changed, 14 insertions(+), 40 deletions(-)

diff --git a/Query-from-Multi-Tables.md b/Query-from-Multi-Tables.md
index 3668bd0..c4b54c5 100644
--- a/Query-from-Multi-Tables.md
+++ b/Query-from-Multi-Tables.md
@@ -78,47 +78,21 @@ fsql.Select<Topic, Category, CategoryType>()
 
 > Experience: [One-to-many, only the last record is taken from the associated table ](https://github.com/dotnetcore/FreeSql/issues/430)
 
-## 3. WithSql
+3、WithoutJoin
+fsql.Select<Order, Product, User>()
+    .InnerJoin((o, p, u) => o.UserId == u.Id)
+    .LeftJoin((o, p, u) => o.ProductId == p.Id)
+    .WithoutJoin(t2: !includeProductInfo)
+    .ToList((o, p, u) => new OrderDetailDto
+    {
+        OrderId = o.Id,
+        OrderNo = o.OrderNo,
+        Username = u.Username, // User (T3) 始终 JOIN，可直接引用
+        ProductName = includeProductInfo ? p.Name : "N/A"
+    });
 
-```csharp
-fsql.Select<Topic, Category, CategoryType>()
-  .WithSql(
-      "select * from Topic where id=@id1",
-      "select * from Category where id=@id2",
-      null, //Do not set the SQL corresponding to CategoryType
-      new { id1 = 10, id2 = 11, id3 = 13 }
-  )
-  .LeftJoin((a,b,c) => a.CategoryId == b.Id)
-  .LeftJoin((a,b,c) => b.ParentId == c.Id)
-  .ToList();
-
-//SELECT ...
-//FROM ( select * from Topic where id=@id1 ) a
-//LEFT JOIN ( select * from Category where id=@id2 ) b ON a.`CategoryId` = b.`Id`
-//LEFT JOIN `CategoryType` c ON b.`ParentId` = c.`Id`
-```
-
-> Tip: `ISelect.ToSql` can be used with `WithSql`
-
-> v3.2.666 [UnionAll Query](%E8%81%94%E5%90%88%E6%9F%A5%E8%AF%A2)、[WithTempQuery + FromQuery Nested Query](%e5%b5%8c%e5%a5%97%e6%9f%a5%e8%af%a2)
-
-> v3.2.666 WithMemory Query using memory data
-
-```csharp
-var list = new List<Topic>();
-list.Add(new Topic { ... });
-list.Add(new Topic { ... });
-
-fsql.Select<Topic>()
-  .WithMemory(list)
-  .ToList()
-//SELECT a.`Id`, a.`Clicks`, a.`CategoryId`, a.`Title`, a.`CreateTime` 
-//FROM (
-//  SELECT ...
-//  UNION ALL
-//  SELECT ...
-//) a 
-```
+// includeProductInfo = true: SQL JOIN Product
+// includeProductInfo = false: SQL will not JOIN Product, ProductName will be "N/A"
 
 ## 4. SQL join table