docs: update from table (#1678)

* Update dml-update.md

* Update dml-update.md

Author: soyeric128

docs/en/sql-reference/10-sql-commands/10-dml/dml-update.md

@@ -1,8 +1,11 @@
 ---
 title: UPDATE
 ---
+import FunctionDescription from '@site/src/components/FunctionDescription';
 
-Modifies rows in a table with new values.
+<FunctionDescription description="Introduced or updated: v1.2.699"/>
+
+Updates rows in a table with new values, optionally using values from other tables.
 
 :::tip atomic operations
 Databend ensures data integrity with atomic operations. Inserts, updates, replaces, and deletes either succeed completely or fail entirely.
@@ -11,45 +14,116 @@ Databend ensures data integrity with atomic operations. Inserts, updates, replac
 ## Syntax
 
 ```sql
-UPDATE <table_name>
-SET <col_name> = <value> [ , <col_name> = <value> , ... ]
-    [ WHERE <condition> ]
+UPDATE <target_table>
+       SET <col_name> = <value> [ , <col_name> = <value> , ... ] -- Set new values  
+        [ FROM <additional_tables> ] -- Use values from other tables  
+        [ WHERE <condition> ] -- Filter rows
 ```
 
 ## Examples
 
+The following example demonstrates how to update rows in a table, both directly and using values from another table. 
+
+We will first create a **bookstore** table and insert some sample data, then update a specific row directly. After that, we will use a second table, **book_updates**, to update rows in the **bookstore** table based on the values from **book_updates**.
+
+#### Step 1: Create the bookstore table and insert initial data
+
+In this step, we create a table called **bookstore** and populate it with some sample book data.
+
 ```sql
--- create a table
 CREATE TABLE bookstore (
   book_id INT,
   book_name VARCHAR
 );
 
--- insert values
 INSERT INTO bookstore VALUES (101, 'After the death of Don Juan');
 INSERT INTO bookstore VALUES (102, 'Grown ups');
 INSERT INTO bookstore VALUES (103, 'The long answer');
 INSERT INTO bookstore VALUES (104, 'Wartime friends');
 INSERT INTO bookstore VALUES (105, 'Deconstructed');
+```
+
+#### Step 2: View the bookstore table before the update
 
--- show the table before update
+We can now check the contents of the **bookstore** table to see the initial data.
+
+```sql
 SELECT * FROM bookstore;
 
-101|After the death of Don Juan
-102|Grown ups
-103|The long answer
-104|Wartime friends
-105|Deconstructed
+┌───────────────────────────────────────────────┐
+│     book_id     │          book_name          │
+├─────────────────┼─────────────────────────────┤
+│             102 │ Grown ups                   │
+│             103 │ The long answer             │
+│             101 │ After the death of Don Juan │
+│             105 │ Deconstructed               │
+│             104 │ Wartime friends             │
+└───────────────────────────────────────────────┘
+```
+
+#### Step 3: Update a single row directly
+
+Next, let's update the book with book_id `103` to change its name.
+
+```sql
+UPDATE bookstore 
+SET book_name = 'The long answer (2nd)' 
+WHERE book_id = 103;
+```
+
+#### Step 4: View the bookstore table after the update
+
+Now, let's check the table again to see the result of our direct update.
+
+```sql
+SELECT book_name FROM bookstore WHERE book_id=103;
+
+┌───────────────────────┐
+│       book_name       │
+├───────────────────────┤
+│ The long answer (2nd) │
+└───────────────────────┘
+```
+
+#### Step 5: Create a new table for updated values
+
+In this step, we create a second table called **book_updates**, which holds updated book names that we will use to update the **bookstore** table.
+
+```sql
+CREATE TABLE book_updates (
+  book_id INT,
+  new_book_name VARCHAR
+);
 
--- Update a book (Id: 103)
-UPDATE bookstore SET book_name = 'The long answer (2nd)' WHERE book_id = 103;
+INSERT INTO book_updates VALUES (103, 'The long answer (Revised)');
+INSERT INTO book_updates VALUES (104, 'Wartime friends (Expanded Edition)');
+```
+
+#### Step 6: Update the bookstore table using values from book_updates
+
+Now, we will update the **bookstore** table with values from the **book_updates** table.
 
--- show the table again after update
+```sql
+UPDATE bookstore
+SET book_name = book_updates.new_book_name
+FROM book_updates
+WHERE bookstore.book_id = book_updates.book_id;
+```
+
+#### Step 7: View the bookstore table after the update
+
+Finally, we check the **bookstore** table again to confirm that the names have been updated using the values from **book_updates**.
+
+```sql
 SELECT * FROM bookstore;
 
-101|After the death of Don Juan
-102|Grown ups
-103|The long answer (2nd)
-104|Wartime friends
-105|Deconstructed
+┌──────────────────────────────────────────────────────┐
+│     book_id     │              book_name             │
+├─────────────────┼────────────────────────────────────┤
+│             105 │ Deconstructed                      │
+│             101 │ After the death of Don Juan        │
+│             102 │ Grown ups                          │
+│             104 │ Wartime friends (Expanded Edition) │
+│             103 │ The long answer (Revised)          │
+└──────────────────────────────────────────────────────┘
 ```