update 优化文档细节及代码格式

docs/zh/base/querywrapper.md

@@ -21,7 +21,7 @@ public class AccountController {
     @GetMapping("/accounts")
     List<Account> selectList() {
         
-        //构造 QueryWrapper
+        //构造 QueryWrapper，也支持使用 QueryWrapper.create() 构造，效果相同
         QueryWrapper query = new QueryWrapper();
         query.where(ACCOUNT.ID.ge(100));
 

docs/zh/intro/comparison.md

@@ -49,8 +49,25 @@ MyBatis-Flex 主要是和 `MyBatis-Plus` 与 `Fluent-Mybatis` 对比，内容来
 
 **MyBatis-Flex：**
 
+一般方式：
 ````java
-QueryCondition condition = EMPLOYEE.LAST_NAME.like("B")
+QueryWrapper query = QueryWrapper.create()
+        .where(EMPLOYEE.LAST_NAME.like(searchWord)) //条件为null时自动忽略
+        .and(EMPLOYEE.GENDER.eq(1))
+        .and(EMPLOYEE.AGE.gt(24));
+List<Employee> employees = employeeMapper.selectListByQuery(query);
+````
+更简单一点：
+````java
+QueryWrapper query = select()
+        .where(EMPLOYEE.LAST_NAME.like(searchWord))
+        .and(EMPLOYEE.GENDER.eq(1))
+        .and(EMPLOYEE.AGE.gt(24));
+List<Employee> employees = employeeMapper.selectListByQuery(query);
+````
+换一种方式：
+````java
+QueryCondition condition = EMPLOYEE.LAST_NAME.like(searchWord)
         .and(EMPLOYEE.GENDER.eq(1))
         .and(EMPLOYEE.AGE.gt(24));
 List<Employee> employees = employeeMapper.selectListByCondition(condition);
@@ -59,19 +76,17 @@ List<Employee> employees = employeeMapper.selectListByCondition(condition);
 **MyBatis-Plus：**
 
 ````java
-QueryWrapper<Employee> queryWrapper = new QueryWrapper<>();
-queryWrapper
-        .like("last_name","B")
+QueryWrapper<Employee> queryWrapper = Wrappers.query()
+        .like(searchWord != null, "last_name", searchWord)
         .eq("gender", 1)
         .gt("age", 24);
 List<Employee> employees = employeeMapper.selectList(queryWrapper);
 ````
-或者 MyBatis-Plus 的另一种写法：
+或者 MyBatis-Plus 的lambda写法：
 
 ```java
-LambdaQueryWrapper<Employee> queryWrapper = new LambdaQueryWrapper<>();
-queryWrapper
-        .like(Employee::getUserName,"B")
+LambdaQueryWrapper<Employee> queryWrapper = Wrappers.<Employee>lambdaQuery()
+        .like(StringUtils.isNotEmpty(searchWord), Employee::getUserName,"B")
         .eq(Employee::getGender, 1)
         .gt(Employee::getAge, 24);
 List<Employee> employees = employeeMapper.selectList(queryWrapper);
@@ -82,7 +97,7 @@ List<Employee> employees = employeeMapper.selectList(queryWrapper);
 
 ````java
 EmployeeQuery query = new EmployeeQuery()
-    .where.lastName().like("B")
+    .where.lastName().like(searchWord, If::notNull)
     .and.gender().eq(1)
     .and.age().gt(24)
     .end();
@@ -96,7 +111,7 @@ List<Employee> employees = employeeMapper.listEntity(query);
 **MyBatis-Flex：**
 
 ````java
-QueryWrapper query = new QueryWrapper()
+QueryWrapper query = QueryWrapper.create()
     .select(
         ACCOUNT.ID,
         ACCOUNT.USER_NAME,
@@ -108,17 +123,16 @@ List<Employee> employees = employeeMapper.selectListByQuery(query);
 **MyBatis-Plus：**
 
 ````java
-QueryWrapper<Employee> queryWrapper = new QueryWrapper<>();
-queryWrapper
+QueryWrapper<Employee> queryWrapper = Wrappers.query()
     .select(
-        "id"
-        ,"user_name"
-        ,"max(birthday)"
-        ,"avg(birthday) as sex_avg"
+        "id",
+        "user_name",
+        "max(birthday)",
+        "avg(birthday) as sex_avg"
     );
 List<Employee> employees = employeeMapper.selectList(queryWrapper);
 ````
-> 缺点：字段硬编码，容易错处。无法使用 ide 的字段进行重构，无法使用 IDE 自动提示，发生错误不能及时发现。
+> 缺点：字段硬编码，容易拼错。无法使用 ide 的字段进行重构，无法使用 IDE 自动提示，发生错误不能及时发现。
 
 
 **Fluent-MyBatis：**
@@ -159,10 +173,15 @@ QueryWrapper query = QueryWrapper.create()
 **MyBatis-Plus：**
 
 ```java
-QueryWrapper<Employee> query = new QueryWrapper<>();
-queryWrapper.ge("id",100)
+QueryWrapper<Employee> query = Wrappers.query()
+        .ge("id", 100)
         .and(i -> i.eq("sex", 1).or(x -> x.eq("sex", 2)))
-        .or(i->i.in("age",{18,19,20}).like("user_name","michael"));
+        .or(i -> i.in("age", 18, 19, 20).like("user_name", "michael"));
+// or lambda
+LambdaQueryWrapper<Employee> query = Wrappers.<Employee>lambdaQuery()
+        .ge(Employee::getId, 100)
+        .and(i -> i.eq(Employee::getSex, 1).or(x -> x.eq(Employee::getSex, 2)))
+        .or(i -> i.in(Employee::getAge, 18, 19, 20).like(Employee::getUserName, "michael"));
 ```
 
 **Fluent-Mybatis：**

readme_zh.md

@@ -88,7 +88,7 @@ class HelloWorld {
 //示例2：通过 QueryWrapper 构建条件查询数据列表
 QueryWrapper query = QueryWrapper.create()
     .select()
-    .from(ACCOUNT)
+    .from(ACCOUNT) // 单表查询时表名可省略，自动使用Mapper泛型对应的表
     .where(ACCOUNT.ID.ge(100))
     .and(ACCOUNT.USER_NAME.like("张").or(ACCOUNT.USER_NAME.like("李")));
 
@@ -96,7 +96,7 @@ QueryWrapper query=QueryWrapper.create()
 // ELECT * FROM tb_account
 // WHERE tb_account.id >=  100
 // AND (tb_account.user_name LIKE '%张%' OR tb_account.user_name LIKE '%李%' )
-List<Account> accounts = mapper.selectListByQuery(query);
+List<Account> accounts = accountMapper.selectListByQuery(query);
 ```
 
 示例3：分页查询
@@ -126,19 +126,29 @@ Page<Account> accounts = mapper.paginate(5,10,query);
 
 ```java
 QueryWrapper query = new QueryWrapper();
-query.select().from(ACCOUNT)
+query.select().from(ACCOUNT);
 
 // SQL: 
 // SELECT * FROM tb_account
 ```
+也可以通过静态方法简写成如下两种形式，效果完全相同：
+```java
+// 方式1
+QueryWrapper query = QueryWrapper.create()
+        .select().from(ACCOUNT);
+// 方式2
+QueryWrapper query = select().from(ACCOUNT);
 
+// SQL: 
+// SELECT * FROM tb_account
+```
 ### select columns
 
 简单示例：
 ```java
 QueryWrapper query = new QueryWrapper();
 query.select(ACCOUNT.ID, ACCOUNT.USER_NAME)
-    .from(ACCOUNT)
+    .from(ACCOUNT);
 
 // SQL: 
 // SELECT id, user_name 
@@ -180,8 +190,9 @@ QueryWrapper query=new QueryWrapper()
 ```
 
 ### where
-
 ```java
+Integer num = 100;
+String userName = "michael";
 QueryWrapper queryWrapper = QueryWrapper.create()
     .select()
     .from(ACCOUNT)
@@ -221,6 +232,21 @@ QueryWrapper queryWrapper = QueryWrapper.create()
 // SELECT * FROM tb_account 
 // WHERE user_name LIKE  ? 
 ```
+### where 自动忽略 null 值
+当遇到条件值为 null 时，会自动忽略该条件，不会拼接到 SQL 中
+```java
+Integer num = null;
+String userName = "michael";
+QueryWrapper queryWrapper = QueryWrapper.create()
+    .select()
+    .from(ACCOUNT)
+    .where(ACCOUNT.ID.ge(num))
+    .and(ACCOUNT.USER_NAME.like(userName));
+
+// SQL: 
+// SELECT * FROM tb_account 
+// WHERE user_name LIKE '%michael%' 
+```
 
 
 ### where select
@@ -466,7 +492,7 @@ set user_name = ?, sex = ? where id = ?
 
 ## 自定义 TypeHandler
 
-使用 @column 注解：
+使用 @Column 注解：
 
 ```java
 @Table("tb_account")
@@ -488,7 +514,6 @@ public class Account {
         }
         options.put(key, value);
     }
-    
 }
 ```