{"id":7835,"date":"2025-09-01T23:04:58","date_gmt":"2025-09-01T15:04:58","guid":{"rendered":"https:\/\/www.legendkiller.xyz\/?p=7835"},"modified":"2025-09-03T10:08:24","modified_gmt":"2025-09-03T02:08:24","slug":"ssm-mybatis","status":"publish","type":"post","link":"https:\/\/www.legendkiller.xyz\/index.php\/2025\/09\/01\/ssm-mybatis\/","title":{"rendered":"SSM-MyBatis\uff08\u5b8c\u7ed3\uff09"},"content":{"rendered":"\n

\u4e09.MyBatis\u7bc7<\/h1>\n\n\n\n

1.\u7b80\u4ecb<\/h2>\n\n\n\n

MyBatis \u662f\u4e00\u4e2a\u534a\u81ea\u52a8\u5316\u7684 ORM\uff08\u5bf9\u8c61\u5173\u7cfb\u6620\u5c04\uff09\u6846\u67b6\uff0c\u5141\u8bb8\u5f00\u53d1\u8005\u624b\u52a8\u7f16\u5199 SQL \u8bed\u53e5\uff0c\u4ece\u800c\u80fd\u591f\u66f4\u597d\u5730\u63a7\u5236 SQL \u7684\u6267\u884c\uff0c\u63d0\u9ad8\u6027\u80fd\u3002MyBatis \u53ef\u4ee5\u5c06 SQL \u8bed\u53e5\u4e0e Java \u4ee3\u7801\u5206\u79bb\uff0c\u5b58\u50a8\u5728 XML \u6587\u4ef6\u6216\u8005\u6ce8\u89e3\u4e2d\uff0c\u8ba9\u4ee3\u7801\u7ed3\u6784\u66f4\u6e05\u6670\u3002<\/p>\n\n\n\n

2.\u521d\u6b65\u4f7f\u7528<\/h2>\n\n\n\n

1.\u5bfc\u5165\u4f9d\u8d56<\/h3>\n\n\n\n
<dependency>\n    <groupId>org.mybatis.spring.boot<\/groupId>\n    <artifactId>mybatis-spring-boot-starter<\/artifactId>\n    <version>3.0.0<\/version>\n<\/dependency><\/code><\/pre>\n\n\n\n
2.\u521b\u5efaDo\u5bf9\u8c61<\/h3>\n\n\n\n
\u6b64\u5904\u4e3a\u57fa\u672c\u6570\u636e\u5bf9\u8c61<\/p>\n\n\n\n
@Data\npublic class EmpDo {\n    private Long id;\n    private S tring name;\n    private Integer age;\n    private String email;\n    private String gender;\n    private String address;\n    private BigDecimal salary;\n}<\/code><\/pre>\n\n\n\n
3.Dao\u5c42\u521b\u5efaMapper\u63a5\u53e3<\/h3>\n\n\n\n
@Mapper\u6ce8\u89e3\u544a\u8bc9mybatis<\/strong>\u8fd9\u662f\u4e00\u4e2aMapper\u63a5\u53e3<\/p>\n\n\n\n
@Mapper\npublic interface EmpMapper {\n    EmpDo getEmpById(Integer id);\n}<\/code><\/pre>\n\n\n\n
4.\u751f\u6210xml\u914d\u7f6e\u6587\u4ef6<\/h3>\n\n\n\n
namespace\u5199Mapper\u5bf9\u8c61\u7684\u5168\u7c7b\u540d<\/p>\n\n\n\n
<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n<!DOCTYPE mapper PUBLIC \"-\/\/mybatis.org\/\/DTD Mapper 3.0\/\/EN\" \"http:\/\/mybatis.org\/dtd\/mybatis-3-mapper.dtd\" >\n<mapper namespace=\"com.zhang.mybatis.dao.EmpMapper\">\n    \/\/\u6b64\u5904\u6dfb\u52a0sql\u65b9\u6cd5\n<\/mapper><\/code><\/pre>\n\n\n\n
\u8fd8\u9700\u8981\u5728application.properties\u4e2d\u6307\u660exml\u914d\u7f6e\u6587\u4ef6\u7684\u4f4d\u7f6e<\/p>\n\n\n\n
mybatis.mapper-locations=classpath:mapper\/**.xml<\/code><\/pre>\n\n\n\n
5.\u7f16\u5199sql<\/h3>\n\n\n\n
<select id=\"getEmpById\" resultType=\"com.zhang.mybatis.bean.EmpDo\">\n    select * from employee where id = #{id}\n<\/select>\n<insert id=\"addEmp\">\n    insert into employee(last_name,email,gender) values (#{lastName},#{email},#{gender})\n<\/insert>\n<update id=\"updateEmp\">\n    update employee set last_name = #{lastName},email = #{email},gender = #{gender} where id = #{id}\n<\/update>\n<delete id=\"deleteEmpById\">\n    delete from employee where id = #{id}\n<\/delete><\/code><\/pre>\n\n\n\n
    \n
  • id\u5bf9\u5e94Mapper\u5bf9\u8c61<\/strong>\u7684\u65b9\u6cd5\u540d<\/li>\n\n\n\n
  • resultType\u5bf9\u5e94\u8fd4\u56de\u503c<\/strong><\/li>\n\n\n\n
  • \u62ec\u53f7\u95f4\u4e3asql\u8bed\u8a00<\/li>\n<\/ul>\n\n\n\n
    \u63a5\u4e0b\u6765\u5c31\u53ef\u4ee5\u76f4\u63a5\u8c03\u7528Mapper\u65b9\u6cd5\u4e86<\/strong><\/p>\n\n\n\n
    6.\u5f00\u542f\u81ea\u589eid<\/h3>\n\n\n\n
    <insert id=\"addEmp\" useGeneratedKeys=\"true\" keyProperty=\"id\"><\/insert><\/code><\/pre>\n\n\n\n
      \n
    • useGeneratedKeys\u8868\u793a\u662f\u5426\u5f00\u59cb\u81ea\u589eid<\/li>\n\n\n\n
    • keyProperty\u6307\u5b9a\u81ea\u52a8\u751f\u6210\u7684id\u5728Do\u4e2d\u5bf9\u5e94\u7684\u5c5e\u6027\uff0c\u628a\u81ea\u52a8\u751f\u6210\u7684id\u5c01\u88c5\u56deEmp\u5bf9\u8c61\u7684id\u5c5e\u6027\u4e2d<\/li>\n<\/ul>\n\n\n\n
      7.\u547d\u540d\u89c4\u5219\u8f6c\u5316<\/h3>\n\n\n\n
      java\u548cmysql\u6570\u636e\u5e93\u91c7\u7528\u4e86\u4e0d\u540c\u7684\u547d\u540d\u89c4\u5219\uff1a<\/p>\n\n\n\n
        \n
      • java\u91c7\u7528\u9a7c\u5cf0\u547d\u540d\uff08userName\uff09<\/li>\n\n\n\n
      • \u6570\u636e\u5e93\u91c7\u7528\u86c7\u5f62\u547d\u540d\uff08user_name\uff09<\/li>\n<\/ul>\n\n\n\n
        \u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u5f00\u542f\u547d\u540d\u89c4\u5219\u81ea\u52a8\u8f6c\u6362\uff0c\u624d\u80fd\u4f7f\u540d\u79f0\u4e00 \u4e00\u5bf9\u5e94\u4e0a<\/p>\n\n\n\n
        mybatis.configuration.map-underscore-to-camel-case=true<\/code><\/pre>\n\n\n\n
        logging.level.com.atguigu.mybatis.mapper=debug\/\/\u5f00SQL\u65e5\u5fd7<\/code><\/pre>\n\n\n\n
        8.\u7ec6\u8282<\/h3>\n\n\n\n
          \n
        • 1. \u6bcf\u4e2aDao \u63a5\u53e3 \u5bf9\u5e94\u4e00\u4e2a XML \u5b9e\u73b0\u6587\u4ef6<\/li>\n\n\n\n
        • 2. Dao \u5b9e\u73b0\u7c7b \u662f\u4e00\u4e2a\u7531 MyBatis \u81ea\u52a8\u521b\u5efa\u51fa\u6765\u7684\u4ee3\u7406\u5bf9\u8c61<\/li>\n\n\n\n
        • 3. XML \u4e2d namespace \u9700\u8981\u7ed1\u5b9a Dao \u63a5\u53e3 \u7684\u5168\u7c7b\u540d<\/li>\n\n\n\n
        • 4. XML \u4e2d\u4f7f\u7528 select\u3001update\u3001insert\u3001delete \u6807\u7b7e\u6765\u4ee3\u8868\u589e\u5220\u6539\u67e5<\/li>\n\n\n\n
        • 5. \u6bcf\u4e2a CRUD \u6807\u7b7e \u7684 id \u5fc5\u987b\u4e3aDao\u63a5\u53e3\u7684\u65b9\u6cd5\u540d<\/li>\n\n\n\n
        • 6. \u6bcf\u4e2a CRUD\u6807\u7b7e\u7684 resultType \u662fDao\u63a5\u53e3\u7684\u8fd4\u56de\u503c\u7c7b\u578b\u5168\u7c7b\u540d<\/li>\n\n\n\n
        • 7. \u672a\u6765\u9047\u5230\u590d\u6742\u7684\u8fd4\u56de\u7ed3\u679c\u5c01\u88c5\uff0c\u9700\u8981\u6307\u5b9a resultMap \u89c4\u5219<\/li>\n\n\n\n
        • 8. \u4ee5\u540e xxxDao \u6211\u4eec\u5c06\u6309\u7167\u4e60\u60ef\u547d\u540d\u4e3a xxxMapper\uff0c\u8fd9\u6837\u66f4\u660e\u663e\u7684\u8868\u793a\u51fa \u6301\u4e45\u5c42\u662f\u7528 MyBatis \u5b9e\u73b0\u7684<\/li>\n<\/ul>\n\n\n\n
          3.\u53c2\u6570\u5904\u7406<\/h2>\n\n\n\n
          \"\"<\/div><\/figure>\n\n\n\n
          1.\u5360\u4f4d\u7b26#{}\u548c${}\u7684\u533a\u522b<\/h3>\n\n\n\n
          select * from employee where id = #{id}\n\nselect * from employee where id = ${id}<\/code><\/pre>\n\n\n\n
          #{}<\/strong> \uff1a\u8fd9\u662fMyBatis\u4e2d\u9884\u7f16\u8bd1\u7684\u5360\u4f4d\u7b26\uff0c\u7528\u4e8e\u5c06\u53c2\u6570\u503c\u5b89\u5168\u5730\u63d2\u5165\u5230SQL\u8bed\u53e5\u4e2d\u3002\u5728SQL\u6267\u884c\u524d\uff0cMyBatis\u4f1a\u5c06#{} \u66ff\u6362\u4e3a?\uff0c\u7136\u540e\u4f7f\u7528PreparedStatement\u6765\u8bbe\u7f6e\u53c2\u6570\u503c\uff0c\u6709\u6548\u9632\u6b62\u4e86sql\u6ce8\u5165\u95ee\u9898\u3002<\/p>\n\n\n\n
          Connection connection = dataSource.getConnection();\nString sql = \"select * from employee where id=?\";\nPreparedStatement ps = connection.prepareStatement(sql);\nps.setString(1, \"admin\");<\/code><\/pre>\n\n\n\n
          ${}\uff1a\u8fd9\u662f\u5b57\u7b26\u4e32\u66ff\u6362\u5360\u4f4d\u7b26\uff0cMyBatis\u4f1a\u76f4\u63a5\u5c06${} \u66ff\u6362\u4e3a\u5b9e\u9645\u7684\u53c2\u6570\u503c\uff0c\u800c\u4e0d\u8fdb\u884c\u9884\u7f16\u8bd1\uff0c\u4f1a\u5f15\u53d1sql\u6ce8\u5165\u95ee\u9898\u3002<\/p>\n\n\n\n
          \u53ea\u6709\u53c2\u6570\u4f4d\u7f6e\u52a8\u6001\u53d6\u503c\u624d\u53ef\u4ee5\u7528#{}\uff0cjdbc\u5c42\u9762\u8868\u540d\u7b49\u4f4d\u7f6e\u4e0d\u652f\u6301\u9884\u7f16\u8bd1\uff0c\u53ea\u80fd\u7528${}\u3002<\/p>\n\n\n\n
          \u603b\u7ed3\uff1a\u80fd\u7528#{}\u5927\u62ec\u53f7\u7684\u5730\u65b9\u5c31\u7528\uff0c\u4e0d\u80fd\u7528#{}\u7684\u5730\u65b9\u7528${}<\/p>\n\n\n\n
          \"\"<\/div><\/figure>\n\n\n\n
          2.\u5355\u53c2\u6570\u53d6\u503c<\/h3>\n\n\n\n
            \n
          • \u5bf9\u8c61\u53d6\u503c\uff1a\u76f4\u63a5\u5199\u5c5e\u6027\u540d\uff0c\u4e0d\u8981\u5199\u5bf9\u8c61\u540d<\/li>\n<\/ul>\n\n\n\n
            select * from employee where id = #{name}<\/code><\/pre>\n\n\n\n
            list\u53d6\u503c\uff1a\u4f7f\u7528\u7d22\u5f15<\/p>\n\n\n\n
            select * from employee where id = #{ids[5]}<\/code><\/pre>\n\n\n\n
            map\u53d6\u503c\uff1a \u4f7f\u7528key\u503c<\/p>\n\n\n\n
            select * from employee where id = #{myId}<\/code><\/pre>\n\n\n\n
            3.\u591a\u53c2\u6570\u53d6\u503c<\/h3>\n\n\n\n
            \u65b0\u7248mybatis<\/strong>\u652f\u6301\u76f4\u63a5\u4f7f\u7528#{\u53c2\u6570\u540d}<\/strong><\/p>\n\n\n\n
            \u8001\u7248mybatis<\/strong>\u9700\u8981\u5728\u53c2\u6570\u524d\u4f7f\u7528@Param<\/strong>\u6307\u5b9a\u53c2\u6570\u540d<\/p>\n\n\n\n
            Emp getEmployByIdAndName(@Param(\"id\") Long id, @Param(\"empName\") Employee emp)<\/code><\/pre>\n\n\n\n
            select * from Employee where id = #{id} and name = #{emp.name}<\/code><\/pre>\n\n\n\n
            \u6700\u4f73\u5b9e\u8df5\uff1a\u5373\u4f7f\u53ea\u6709\u4e00\u4e2a\u53c2\u6570\uff0c\u4e5f\u7528 @Param \u6307\u5b9a\u53c2\u6570\u540d<\/p>\n\n\n\n
            4.\u8fd4\u56de\u503c-\u7ed3\u679c\u5c01\u88c5<\/h2>\n\n\n\n
            1.\u4e00\u822c\u8fd4\u56de\uff1a<\/h3>\n\n\n\n
            <select id=\"getEmpById\" resultType=\"com.zhang.mybatis.bean.EmpDo\">\n    select * from employee where id = #{id}\n<\/select><\/code><\/pre>\n\n\n\n
            resultType\u89c4\u5b9a\u8fd4\u56de\u503c\u7c7b\u578b<\/p>\n\n\n\n
            \"\"<\/div><\/figure>\n\n\n\n
            \"\"<\/div><\/figure>\n\n\n\n
            2.\u8fd4\u56demap\uff1a<\/h3>\n\n\n\n
            \"\"<\/div><\/figure>\n\n\n\n
            mapper\u65b9\u6cd5\u4e2d\u4f7f\u7528@Mapper(“”)<\/strong>\u6307\u5b9akey\u503c\uff0ckey\u9ed8\u8ba4\u4ece\u5bf9\u8c61\u5c5e\u6027\u503c\u4e2d\u53d6<\/p>\n\n\n\n
            @Mapper(\"id\")\/\/\u5c06id\u4f5c\u4e3akey\u503c\nMap<Integer,Emp> getAllMap();<\/code><\/pre>\n\n\n\n
            \u8fd4\u56de\u503c\u7684value\u5b9e\u9645\u4e0a\u4e0d\u662f\u6307\u5b9a\u7c7b(Emp)\uff0c\u800c\u662f\u4e00\u4e2aHashMap<\/strong>,<\/p>\n\n\n\n
            resultType\u4e0d\u5199map\uff0c\u5199\u6307\u5b9a\u7c7b\uff0cvalue\u503c\u624d\u4e3a\u6307\u5b9a\u7c7b<\/p>\n\n\n\n
            3.\u81ea\u5b9a\u4e49\u7ed3\u679c\u96c6- ResultMap<\/h3>\n\n\n\n
            \u6570\u636e\u5e93\u7684\u5b57\u6bb5 \u5982\u679c\u548c Bean\u7684\u5c5e\u6027 \u4e0d\u80fd\u4e00\u4e00\u5bf9\u5e94\uff0c\u6709\u4e24\u79cd\u529e\u6cd5<\/p>\n\n\n\n
              \n
            • 1\u3001\u5982\u679c\u7b26\u5408\u9a7c\u5cf0\u547d\u540d\uff0c\u5219\u5f00\u542f\u9a7c\u5cf0\u547d\u540d\u89c4\u5219<\/li>\n\n\n\n
            • 2\u3001\u7f16\u5199\u81ea\u5b9a\u4e49\u7ed3\u679c\u96c6\uff08ResultMap\uff09 \u8fdb\u884c\u5c01\u88c5<\/li>\n<\/ul>\n\n\n\n
              <resultMap id=\"EmpResultMap\" type=\"com.atguigu.mybatis.entity.Employee\">\n        <id column=\"emp_id\" property=\"empId\"\/>\n        <result column=\"emp_name\" property=\"empName\"\/>\n        <result column=\"emp_salary\" property=\"empSalary\"\/>\n    <\/resultMap>\n<\/code><\/pre>\n\n\n\n
              \u9ed8\u8ba4\u5c01\u88c5\u89c4\u5219(resultType)\uff1a<\/strong>JavaBean\u4e2d\u7684\u5c5e\u6027\u540d \u53bb\u6570\u636e\u5e93\u8868\u4e2d \u627e\u5bf9\u5e94\u5217\u540d\u7684\u503c\uff0c\u4e00\u4e00\u6620\u5c04\u5c01\u88c5\u3002<\/p>\n\n\n\n
              \u81ea\u5b9a\u4e49\u5c01\u88c5\u89c4\u5219(resultMap)\uff1a<\/strong>\u660e\u786e\u6307\u5b9a\u6bcf\u4e00\u5217\u5982\u4f55\u5c01\u88c5\u5230JavaBean\u4e2d<\/p>\n\n\n\n
                \n
              • id \u6807\u7b7e\uff1a\u5fc5\u987b\u6307\u5b9a\u4e3b\u952e\u5217\u6620\u5c04\u89c4\u5219<\/li>\n\n\n\n
              • result \u6807\u7b7e\uff1a\u6307\u5b9a\u666e\u901a\u5217\u6620\u5c04\u89c4\u5219<\/li>\n\n\n\n
              • collection \u6807\u7b7e\uff1a\u6307\u5b9a\u81ea\u5b9a\u4e49\u96c6\u5408\u5c01\u88c5\u89c4\u5219<\/li>\n\n\n\n
              • association \u6807\u7b7e\uff1a\u6307\u5b9a\u81ea\u5b9a\u4e49\u5bf9\u8c61\u5c01\u88c5\u89c4\u5219<\/li>\n<\/ul>\n\n\n\n
                <resultMap id=\"EmpRM\" type=\"com.zhang.mybatis.bean.EmpDo\">\n    <!--\u58f0\u660e\u4e3b\u952e\u6620\u5c04\u89c4\u5219-->\n        <id property=\"id\" column=\"id\"><\/id>\n    <!--\u58f0\u660e\u666e\u901a\u5217\u6620\u5c04\u89c4\u5219-->\n        <result property=\"name\" column=\"name\"><\/result>\n        <result property=\"age\" column=\"age\"><\/result>\n<\/resultMap><\/code><\/pre>\n\n\n\n
                \u5728\u65b9\u6cd5\u4e2d\u6839\u636eResultMap\u7684id\u4f7f\u7528\u5bf9\u7167\u89c4\u5219<\/p>\n\n\n\n
                <select id=\"getEmpById\" resultMap=\"EmpRM\">\n    select * from employee where id = #{id}\n<\/select><\/code><\/pre>\n\n\n\n
                4.\u5173\u8054\u67e5\u8be2<\/h2>\n\n\n\n
                \u4e00\u5bf9\u4e00\u5173\u7cfb\u5c01\u88c5<\/h3>\n\n\n\n
                  \n
                • association \u6807\u7b7e\uff1a\u6307\u5b9a\u81ea\u5b9a\u4e49\u5bf9\u8c61\u5c01\u88c5\u89c4\u5219\uff0c\u4e00\u822c\u7528\u6237\u8054\u5408\u67e5\u8be2\u4e00\u5bf9\u4e00\u5173\u7cfb\u7684\u5c01\u88c5\u3002\u6bd4\u5982\u4e00\u4e2a\u7528\u6237\u5bf9\u5e94\u4e00\u4e2a\u8ba2\u5355\n
                    \n
                  • javaType\uff1a\u6307\u5b9a\u5173\u8054\u7684Bean\u7684\u7c7b\u578b<\/li>\n\n\n\n
                  • select\uff1a\u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u8c03\u7528\u7684\u65b9\u6cd5<\/li>\n\n\n\n
                  • column\uff1a\u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u4f20\u9012\u7684\u53c2\u6570\u5217<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                    \u6309\u7167id\u67e5\u8be2\u8ba2\u5355\u4ee5\u53ca\u4e0b\u5355\u7684\u5ba2\u6237\u4fe1\u606f<\/p>\n\n\n\n
                    <select id=\"getOrderById\" resultType=\"com.zhang.mybatis.bean.Order\">\n    select * from orders\n    left join customer on orders.customer_id = customer.id\n    where orders.id = #{id}\n<\/select><\/code><\/pre>\n\n\n\n
                    \u4f7f\u7528\u9ed8\u8ba4\u5c01\u88c5(resultType)\u65e0\u6cd5\u5c06\u8fde\u63a5\u7684\u5bf9\u8c61\u6b63\u786e\u88c5\u586b(customer\u5c06\u8fd4\u56de\u4e3anull)<\/p>\n\n\n\n
                    Order(id=1, address=chengdu, amount=5000, customerId=1, customer=null)<\/code><\/pre>\n\n\n\n
                    \u8fd9\u65f6\u5019\u8981\u5728\u81ea\u5b9a\u4e49\u5c01\u88c5(resultMap)\u4e2d\u4f7f\u7528association\u6807\u7b7e<\/strong><\/p>\n\n\n\n
                    <resultMap id=\"OrderRM\" type=\"com.zhang.mybatis.bean.Order\">\n    <id property=\"id\" column=\"id\"><\/id>\n    <result property=\"address\" column=\"address\"><\/result>\n    <result property=\"amount\" column=\"amount\"><\/result>\n    <result column=\"customer_id\" property=\"customerId\"><\/result>\n    <association property=\"customer\" javaType=\"com.zhang.mybatis.bean.Customer\">\n        <id property=\"id\" column=\"id\"><\/id>\n        <result property=\"name\" column=\"name\"><\/result>\n    <\/association>\n<\/resultMap><\/code><\/pre>\n\n\n\n
                    \u5de6\u8fde\u63a5\u65f6\uff0cassociation\u6807\u7b7e<\/strong>\u4e2d\u5b9a\u4e49\u4e86\u53f3\u8868\u7684\u5c01\u88c5\u5173\u7cfb<\/p>\n\n\n\n
                    \u4e00\u5bf9\u591a\u5173\u7cfb\u5c01\u88c5<\/h3>\n\n\n\n
                      \n
                    • collection \u6807\u7b7e\uff1a\u6307\u5b9a\u81ea\u5b9a\u4e49\u5bf9\u8c61\u5c01\u88c5\u89c4\u5219\uff0c\u4e00\u822c\u7528\u6237\u8054\u5408\u67e5\u8be2\u4e00\u5bf9\u4e00\u5173\u7cfb\u7684\u5c01\u88c5\u3002\u6bd4\u5982\u4e00\u4e2a\u7528\u6237\u5bf9\u5e94\u4e00\u4e2a\u8ba2\u5355\n
                        \n
                      • ofType\uff1a\u6307\u5b9a\u96c6\u5408\u4e2d\u6bcf\u4e2a\u5143\u7d20\u7684\u7c7b\u578b<\/li>\n\n\n\n
                      • select\uff1a\u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u8c03\u7528\u7684\u65b9\u6cd5<\/li>\n\n\n\n
                      • column\uff1a\u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u4f20\u9012\u7684\u53c2\u6570\u5217<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                        \u6309\u7167id\u67e5\u8be2\u5ba2\u6237\u4ee5\u53ca\u4e0b\u7684\u6240\u6709\u8ba2\u5355<\/p>\n\n\n\n
                        <resultMap id=\"CustomerRM\" type=\"com.zhang.myb atis.bean.Customer\">\n    <id property=\"id\" column=\"id\"><\/id>\n    <result property=\"name\" column=\"name\"><\/result>\n    <collection property=\"orders\" ofType=\"com.zhang.mybatis.bean.Order\">\n        <id property=\"id\" column=\"id\"><\/id>\n        <result property=\"address\" column=\"address\"><\/result>\n        <result property=\"amount\" column=\"amount\"><\/result>\n        <result column=\"customer_id\" property=\"customerId\"><\/result>\n    <\/collection>\n<\/resultMap><\/code><\/pre>\n\n\n\n
                        property\u5bf9\u5e94\u96c6\u5408\uff0cofType\u5bf9\u5e94\u5355\u4e00\u7c7b<\/p>\n\n\n\n
                        5.\u5206\u6b65\u67e5\u8be2<\/h2>\n\n\n\n
                          \n
                        • \u5728 association \u548c collection \u7684\u5c01\u88c5\u8fc7\u7a0b\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528 select + column \u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u903b\u8f91\n
                            \n
                          • select\uff1a\u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u8c03\u7528\u7684\u65b9\u6cd5<\/li>\n\n\n\n
                          • column\uff1a\u6307\u5b9a\u5206\u6b65\u67e5\u8be2\u4f20\u9012\u7684\u53c2\u6570\n
                              \n
                            • \u4f20\u9012\u5355\u4e2a\uff1a\u76f4\u63a5\u5199\u5217\u540d\uff0c\u8868\u793a\u5c06\u8fd9\u5217\u7684\u503c\u4f5c\u4e3a\u53c2\u6570\u4f20\u9012\u7ed9\u4e0b\u4e00\u4e2a\u67e5\u8be2<\/li>\n\n\n\n
                            • \u4f20\u9012\u591a\u4e2a\uff1acolumn=”{prop1=col1,prop2=col2}”\uff0c\u4e0b\u4e00\u4e2a\u67e5\u8be2\u4f7f\u7528prop1\u3001prop2\u53d6\u503c<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                              1.\u624b\u52a8\u5206\u6b65\u67e5\u8be2<\/h3>\n\n\n\n
                              \/\/\u6309\u7167id\u67e5\u8be2\u8ba2\u5355\nOrder order = orderDao.getOrderById(1);\n\/\/\u4f7f\u7528\u8ba2\u5355\u4e2d\u7684\u7528\u6237id\u67e5\u8be2\u7528\u6237\nCustomer customer = OrderDao.getCustomerById(order.getCustomerId());\n\/\/\u5c06\u7528\u6237\u8bbe\u7f6e\u5230\u8ba2\u5355\u4e2d\norder.setCustomer(customer);<\/code><\/pre>\n\n\n\n
                              2.\u81ea\u52a8\u5206\u6b65\u67e5\u8be2<\/h3>\n\n\n\n
                              <resultMap id=\"OrderRM\" type=\"com.zhang.mybatis.bean.Order\">\n        <id property=\"id\" column=\"id\"><\/id>\n        <result property=\"address\" column=\"address\"><\/result>\n        <result property=\"amount\" column=\"amount\"><\/result>\n        <result property=\"customerId\" column=\"customer_id\"><\/result>\n        \n        <collection property=\"customers\"\n                    select=\"com.zhang.mybatis.dao.OrderDao.getCustomerById\"\n                    column=\"customer_id\">\n        <\/collection>\n        \n    <\/resultMap><\/code><\/pre>\n\n\n\n
                                \n
                              • \u5728collection<\/strong>\u6216\u8005association<\/strong>\u4e2d\u4f7f\u7528select<\/strong>\u5c5e\u6027\u544a\u8bc9mybatis\u5728\u88c5\u586b\u8be5\u9879\u65f6\u4f7f\u7528\u53e6\u4e00\u4e2a\u67e5\u8be2\u65b9\u6cd5<\/strong><\/li>\n\n\n\n
                              • column<\/strong>\u6307\u5b9a\u4f20\u9012\u7684\u53c2\u6570\uff0c\u5f53\u51fa\u73b0\u591a\u4e2a\u53c2\u6570\u65f6\uff0c\u4f7f\u7528\u4ee5\u4e0b\u683c\u5f0f<\/li>\n<\/ul>\n\n\n\n
                                column=\"{userName=user_name,userAge=user_age}\"<\/code><\/pre>\n\n\n\n
                                3.\u8d85\u7ea7\u5206\u6b65\u95ee\u9898<\/h3>\n\n\n\n
                                \u95ee\u9898\uff1a\u5f53\u5b9e\u4f53\u7c7b\u4e4b\u95f4\u5b58\u5728\u5faa\u73af\u5f15\u7528\u65f6\uff0c\u4f8b\u5982 A \u7c7b\u5173\u8054 B \u7c7b\uff0cB \u7c7b\u53c8\u5173\u8054 A \u7c7b\uff0c\u5206\u6b65\u67e5\u8be2\u53ef\u80fd\u4f1a\u9677\u5165\u65e0\u9650\u5faa\u73af\uff0c\u6700\u7ec8\u5bfc\u81f4\u6808\u6ea2\u51fa\u9519\u8bef\u3002<\/p>\n\n\n\n
                                \u89e3\u51b3\u529e\u6cd5\uff1a\u4f7f\u7528\u5d4c\u5957\u67e5\u8be2\uff0c\u628a\u5206\u6b65\u67e5\u8be2\u6539\u6210\u5d4c\u5957\u67e5\u8be2\uff0c\u5728\u4e00\u4e2a SQL \u8bed\u53e5\u91cc\u5b8c\u6210\u6240\u6709\u5173\u8054\u67e5\u8be2\u3002\u4e0d\u8fc7\u8fd9\u6837\u53ef\u80fd\u4f1a\u8ba9 SQL \u8bed\u53e5\u53d8\u5f97\u590d\u6742\uff0c\u964d\u4f4e\u53ef\u8bfb\u6027\u3002
                                <\/p>\n\n\n\n
                                6.\u5ef6\u8fdf\u52a0\u8f7d<\/h2>\n\n\n\n
                                  \n
                                • \u5206\u6b65\u67e5\u8be2 \u6709\u65f6\u5019\u5e76\u4e0d\u9700\u8981\u7acb\u5373\u8fd0\u884c\uff0c\u6211\u4eec\u5e0c\u671b\u5728\u7528\u5230\u7684\u65f6\u5019\u518d\u53bb\u67e5\u8be2\uff0c\u53ef\u4ee5\u5f00\u542f\u5ef6\u8fdf\u52a0\u8f7d\u7684\u529f\u80fd\n
                                    \n
                                  • \u5168\u5c40\u914d\u7f6e\uff1a\n
                                      \n
                                    • mybatis.configuration.lazy-loading-enabled=true\/\/\u5f00\u542f MyBatis \u7684\u5ef6\u8fdf\u52a0\u8f7d\u7279\u6027\u3002<\/li>\n\n\n\n
                                    • mybatis.configuration.aggressive-lazy-loading=false\/\/\u7981\u7528\u79ef\u6781\u5ef6\u8fdf\u52a0\u8f7d\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                                      7.\u52a8\u6001sql<\/h2>\n\n\n\n
                                      1.\u7b80\u4ecb<\/h3>\n\n\n\n
                                        \n
                                      • \u52a8\u6001 SQL \u662f MyBatis \u7684\u5f3a\u5927\u7279\u6027\u4e4b\u4e00\u3002\u5982\u679c\u4f60\u4f7f\u7528\u8fc7 JDBC \u6216\u5176\u5b83\u7c7b\u4f3c\u7684\u6846\u67b6\uff0c\u4f60\u5e94\u8be5\u80fd\u7406\u89e3\u6839\u636e\u4e0d\u540c\u6761\u4ef6\u62fc\u63a5 SQL \u8bed\u53e5\u6709\u591a\u75db\u82e6\uff0c\u4f8b\u5982\u62fc\u63a5\u65f6\u8981\u786e\u4fdd\u4e0d\u80fd\u5fd8\u8bb0\u6dfb\u52a0\u5fc5\u8981\u7684\u7a7a\u683c\uff0c\u8fd8\u8981\u6ce8\u610f\u53bb\u6389\u5217\u8868\u6700\u540e\u4e00\u4e2a\u5217\u540d\u7684\u9017\u53f7\u3002\u5229\u7528\u52a8\u6001 SQL\uff0c\u53ef\u4ee5\u5f7b\u5e95\u6446\u8131\u8fd9\u79cd\u75db\u82e6\u3002<\/li>\n\n\n\n
                                      • \u4f7f\u7528\u52a8\u6001 SQL \u5e76\u975e\u4e00\u4ef6\u6613\u4e8b\uff0c\u4f46\u501f\u52a9\u53ef\u7528\u4e8e\u4efb\u4f55 SQL \u6620\u5c04\u8bed\u53e5\u4e2d\u7684\u5f3a\u5927\u7684\u52a8\u6001 SQL \u8bed\u8a00\uff0cMyBatis \u663e\u8457\u5730\u63d0\u5347\u4e86\u8fd9\u4e00\u7279\u6027\u7684\u6613\u7528\u6027\u3002<\/li>\n<\/ul>\n\n\n\n
                                        mybatis\u4e2d\u52a8\u6001sql \u9ed8\u8ba4\u4e8b\u52a1\u56de\u6eda\u5f00\u542f<\/p>\n\n\n\n
                                          \n
                                        1. \u771f\u6b63\u548c\u4e8b\u52a1\u76f8\u5173\u7684\u4e0d\u662f MyBatis\uff0c\u800c\u662f\u5b83\u8fd0\u884c\u6240\u5728\u7684\u73af\u5883\u3002<\/li>\n\n\n\n
                                        2. \u6bd4\u5982\u5728 Spring \u4e2d\uff0c@Transactional<\/code> \u6ce8\u89e3\u4f1a\u5f00\u542f\u4e8b\u52a1\uff0c\u51fa\u73b0 \u8fd0\u884c\u65f6\u5f02\u5e38 (RuntimeException) \u6216 Error<\/strong> \u65f6\uff0c\u9ed8\u8ba4\u4f1a\u81ea\u52a8\u56de\u6eda\u3002<\/li>\n\n\n\n
                                        3. MyBatis \u5728 \u539f\u751f\u4f7f\u7528 SqlSession<\/strong> \u65f6\uff0c\u4e5f\u4f1a\u5728\u4f60\u6ca1\u6709\u663e\u5f0f\u8c03\u7528 commit()<\/code> \u4e4b\u524d\uff0c\u9ed8\u8ba4\u5904\u4e8e\u4e00\u4e2a\u4e8b\u52a1\u4e2d\uff08\u4e0d\u81ea\u52a8\u63d0\u4ea4\uff09\u3002\u5982\u679c\u6267\u884c\u51fa\u9519\uff0c\u5b83\u4f1a\u56de\u6eda\u3002<\/li>\n<\/ol>\n\n\n\n
                                            \n
                                          • \u52a8\u6001 SQL \u53ea\u662f\u62fc\u63a5 SQL\uff0c\u4e0d\u5f71\u54cd\u4e8b\u52a1\uff1b<\/strong><\/li>\n\n\n\n
                                          • MyBatis \u7684 SqlSession<\/code> \u9ed8\u8ba4\u4e0d\u4f1a\u81ea\u52a8\u63d0\u4ea4\u4e8b\u52a1\uff0c\u53ea\u6709\u5728\u8c03\u7528 commit()<\/code> \u65f6\u624d\u63d0\u4ea4\uff1b<\/li>\n\n\n\n
                                          • \u5982\u679c\u5728\u6267\u884c\u8fc7\u7a0b\u4e2d\u629b\u51fa\u5f02\u5e38\uff08\u6bd4\u5982 SQL \u62fc\u63a5\u9519\u8bef\u3001\u6570\u636e\u5e93\u7ea6\u675f\u5f02\u5e38\uff09\uff0c\u4e8b\u52a1\u5c31\u4f1a\u56de\u6eda\uff1b<\/li>\n\n\n\n
                                          • \u5728 Spring + MyBatis \u4e2d\uff0c\u5982\u679c\u7528\u4e86 @Transactional<\/code>\uff0cSpring \u4f1a\u63a5\u7ba1\u4e8b\u52a1\u7ba1\u7406\uff0c\u9ed8\u8ba4\u89c4\u5219\u540c\u6837\u662f\u8fd0\u884c\u65f6\u5f02\u5e38\u89e6\u53d1\u56de\u6eda\u3002<\/li>\n<\/ul>\n\n\n\n
                                            2.\u6807\u7b7e<\/h3>\n\n\n\n
                                            if\u3001where \u6807\u7b7e<\/h4>\n\n\n\n
                                              \n
                                            • \u9700\u6c42\uff1a\u6309\u7167 empName \u548c empSalary \u67e5\u8be2\u5458\u5de5\u3002<\/li>\n\n\n\n
                                            • \u6ce8\u610f\uff1a\u524d\u7aef\u4e0d\u4e00\u5b9a\u643a\u5e26\u6240\u6709\u6761\u4ef6<\/li>\n<\/ul>\n\n\n\n
                                                  <select id=\"selectEmployeeByCondition\" resultType=\"employee\">\n        select emp_id,emp_name,emp_salary from t_emp\n        <where>\n            <if test=\"empName != null\">\n                or emp_name=#{empName}\n            <\/if>\n            <if test=\"empSalary !=null\">\n                or emp_salary>#{empSalary}\n            <\/if>\n        <\/where>\n    <\/select>\n<\/code><\/pre>\n\n\n\n
                                              set\u6807\u7b7e<\/h4>\n\n\n\n
                                                \n
                                              • \u9700\u6c42\uff1a\u4fee\u6539 empName \u548c empSalary<\/li>\n\n\n\n
                                              • \u6ce8\u610f\uff1a\u524d\u7aef\u4e0d\u4e00\u5b9a\u643a\u5e26\u6240\u6709\u6761\u4ef6<\/li>\n<\/ul>\n\n\n\n
                                                    <update id=\"updateEmployeeDynamic\">\n        update t_emp\n        <set>\n            <if test=\"empName != null\">\n                emp_name=#{empName},\n            <\/if>\n            <if test=\"empSalary &lt; 3000\">\n                emp_salary=#{empSalary},\n            <\/if>\n        <\/set>\n        where emp_id=#{empId}\n    <\/update>\n<\/code><\/pre>\n\n\n\n
                                                trim\u6807\u7b7e<\/h4>\n\n\n\n
                                                trim \u53ef\u4ee5\u5b9e\u73b0 set \u53bb\u6389\u591a\u4f59\u9017\u53f7\uff0cwhere \u53bb\u6389\u591a\u4f59and\/or \u7684\u529f\u80fd\uff0c \u4e0d\u8fc7\u5199\u8d77\u6765\u6bd4\u8f83\u9ebb\u70e6<\/p>\n\n\n\n
                                                <select id=\"selectEmployeeByConditionByTrim\" resultType=\"com.atguigu.mybatis.entity.Employee\">\n        select emp_id,emp_name,emp_age,emp_salary,emp_gender from t_emp\n        <trim prefix=\"where\" suffixOverrides=\"and|or\">\n            <if test=\"empName != null\">\n                emp_name=#{empName} and\n            <\/if>\n            <if test=\"empSalary &gt; 3000\">\n                emp_salary>#{empSalary} and\n            <\/if>\n            <if test=\"empAge &lt;= 20\">\n                emp_age=#{empAge} or\n            <\/if>\n            <if test=\"empGender=='male'\">\n                emp_gender=#{empGender}\n            <\/if>\n        <\/trim>\n    <\/select><\/code><\/pre>\n\n\n\n
                                                \u5f53\u6807\u7b7e\u4e2d\u5b58\u5728\u5185\u5bb9\u65f6\uff0c\u4e3a\u8be5\u5185\u5bb9\u6dfb\u52a0\u524d\u7f00\uff08prefix\uff09<\/strong>\u6216\u8005\u540e\u7f00\uff08suffix\uff09<\/strong><\/p>\n\n\n\n
                                                <trim prefix=\"\u524d\u7f00\" suffix=\"\u540e\u7f00\"><\/trim><\/code><\/pre>\n\n\n\n
                                                \u6807\u7b7e\u4f53\u4e2d\u6700\u7ec8\u751f\u6210\u7684\u5b57\u7b26\u4e32\u5982\u679c\u4ee5\u6307\u5b9a\u524d\u7f00\uff08prefixOverrides\uff09<\/strong>\u6216\u8005\u540e\u7f00\uff08suffixOverrides\uff09<\/strong>\u5f00\u59cb\uff0c\u5c31\u5c06\u8be5\u524d\u7f00\u8986\u76d6\u4e3a\u7a7a\u4e32<\/strong><\/p>\n\n\n\n
                                                <trim prefixOverrides=\"\u524d\u7f00\" suffixOverrides=\"\u540e\u7f00\"><\/trim><\/code><\/pre>\n\n\n\n
                                                choose\/when\/otherwise\u6807\u7b7e<\/h4>\n\n\n\n
                                                  \n
                                                • \u5728\u591a\u4e2a\u5206\u652f\u6761\u4ef6\u4e2d\uff0c\u4ec5\u6267\u884c\u4e00\u4e2a\u3002<\/li>\n<\/ul>\n\n\n\n
                                                      <select id=\"selectEmployeeByConditionByChoose\" \n                  resultType=\"com.atguigu.mybatis.entity.Employee\">\n        select emp_id,emp_name,emp_salary from t_emp where\n        <choose>\n            <when test=\"empName != null\">emp_name=#{empName}<\/when>\n            <when test=\"empSalary &lt; 3000\">emp_salary &lt; 3000<\/when>\n            <otherwise>1=1<\/otherwise>\n        <\/choose>\n    <\/select>\n<\/code><\/pre>\n\n\n\n
                                                  <choose>\uff1a\u4f5c\u4e3a\u6839\u6807\u7b7e\uff0c\u5305\u88f9\u591a\u4e2a <when> \u548c\u4e00\u4e2a\u53ef\u9009\u7684 <otherwise> \u6807\u7b7e\uff0c\u7528\u4e8e\u8868\u793a\u4e00\u7ec4\u6761\u4ef6\u9009\u62e9\u903b\u8f91\u3002<\/p>\n\n\n\n
                                                  <choose>\n    <when test=\"condition1\">\n        <!-- SQL \u7247\u6bb5 1 -->\n    <\/when>\n    <when test=\"condition2\">\n        <!-- SQL \u7247\u6bb5 2 -->\n    <\/when>\n    <!-- \u53ef\u4ee5\u6709\u591a\u4e2a <when> \u6807\u7b7e -->\n    <otherwise>\n        <!-- \u9ed8\u8ba4 SQL \u7247\u6bb5 -->\n    <\/otherwise>\n<\/choose><\/code><\/pre>\n\n\n\n
                                                  foreach\u6807\u7b7e<\/h4>\n\n\n\n
                                                    \n
                                                  • \u7528\u6765\u904d\u5386\uff0c\u5faa\u73af\uff1b\u5e38\u7528\u4e8e\u6279\u91cf\u63d2\u5165\u573a\u666f\uff1b\u6279\u91cf\u5355\u4e2aSQL<\/li>\n<\/ul>\n\n\n\n
                                                    <!--\n    collection\u5c5e\u6027\uff1a\u8981\u904d\u5386\u7684\u96c6\u5408\n    item\u5c5e\u6027\uff1a\u904d\u5386\u96c6\u5408\u7684\u8fc7\u7a0b\u4e2d\u80fd\u5f97\u5230\u6bcf\u4e00\u4e2a\u5177\u4f53\u5bf9\u8c61\uff0c\u5728item\u5c5e\u6027\u4e2d\u8bbe\u7f6e\u4e00\u4e2a\u540d\u5b57\uff0c\u5c06\u6765\u901a\u8fc7\u8fd9\u4e2a\u540d\u5b57\u5f15\u7528\u904d\u5386\u51fa\u6765\u7684\u5bf9\u8c61\n    separator\u5c5e\u6027\uff1a\u6307\u5b9a\u5f53foreach\u6807\u7b7e\u7684\u6807\u7b7e\u4f53\u91cd\u590d\u62fc\u63a5\u5b57\u7b26\u4e32\u65f6\uff0c\u5404\u4e2a\u6807\u7b7e\u4f53\u5b57\u7b26\u4e32\u4e4b\u95f4\u7684\u5206\u9694\u7b26\n    open\u5c5e\u6027\uff1a\u6307\u5b9a\u6574\u4e2a\u5faa\u73af\u628a\u5b57\u7b26\u4e32\u62fc\u597d\u540e\uff0c\u5b57\u7b26\u4e32\u6574\u4f53\u7684\u524d\u9762\u8981\u6dfb\u52a0\u7684\u5b57\u7b26\u4e32\n    close\u5c5e\u6027\uff1a\u6307\u5b9a\u6574\u4e2a\u5faa\u73af\u628a\u5b57\u7b26\u4e32\u62fc\u597d\u540e\uff0c\u5b57\u7b26\u4e32\u6574\u4f53\u7684\u540e\u9762\u8981\u6dfb\u52a0\u7684\u5b57\u7b26\u4e32\n    index\u5c5e\u6027\uff1a\u8fd9\u91cc\u8d77\u4e00\u4e2a\u540d\u5b57\uff0c\u4fbf\u4e8e\u540e\u9762\u5f15\u7528\n        \u904d\u5386List\u96c6\u5408\uff0c\u8fd9\u91cc\u80fd\u591f\u5f97\u5230List\u96c6\u5408\u7684\u7d22\u5f15\u503c\n        \u904d\u5386Map\u96c6\u5408\uff0c\u8fd9\u91cc\u80fd\u591f\u5f97\u5230Map\u96c6\u5408\u7684key\n -->\n<foreach collection=\"empList\" item=\"emp\" separator=\",\" open=\"values\" index=\"myIndex\">\n    (#{emp.empName},#{myIndex},#{emp.empSalary},#{emp.empGender})\n<\/foreach>\n<\/code><\/pre>\n\n\n\n
                                                      \n
                                                    • IN\u5b50\u53e5\uff1a\u67e5\u8be2\u591aID\u8bb0\u5f55\uff0c\u751f\u6210\u5982 (id1, id2)\u3002<\/li>\n<\/ul>\n\n\n\n
                                                      <select id=\"getOrdersByIds\" resultMap=\"OrderRM\">\n    SELECT * FROM orders\n    WHERE id IN\n    <foreach item=\"item\" index=\"index\" collection=\"orderIds\"\n             open=\"(\" separator=\",\" close=\")\">\n        #{item}\n    <\/foreach>\n<\/select><\/code><\/pre>\n\n\n\n
                                                        \n
                                                      • \u6279\u91cf\u63d2\u5165\uff1a\u751f\u6210\u591a\u4e2a VALUES \u5b50\u53e5\u3002<\/li>\n<\/ul>\n\n\n\n
                                                        <insert id=\"batchInsertOrders\">\n    INSERT INTO orders (address, amount, customer_id)\n    VALUES\n    <foreach item=\"order\" index=\"index\" collection=\"orderList\"\n             separator=\",\">\n        (#{order.address}, #{order.amount}, #{order.customerId})\n    <\/foreach>\n<\/insert><\/code><\/pre>\n\n\n\n
                                                          \n
                                                        • \u6279\u91cf\u66f4\u65b0\uff1a\u7ed3\u5408 CASE WHEN \u8bed\u53e5\u3002<\/li>\n<\/ul>\n\n\n\n
                                                          <update id=\"batchUpdateOrders\">\n    <foreach collection=\"emps\" item=\"e\" separator=\";\">\n    \tupdate t_emp set emp_name = #{e.empName} where id = #{e.id}\n    <\/foreach>\n<\/update><\/code><\/pre>\n\n\n\n
                                                          sql\u7247\u6bb5<\/h4>\n\n\n\n
                                                          \u2022\u62bd\u53d6\u53ef\u4ee5\u590d\u7528\u7684SQL\u7247\u6bb5<\/p>\n\n\n\n
                                                              <sql id=\"empColumn\">\n         emp_id,emp_name,emp_age,emp_salary,emp_gender\n    <\/sql>\n\n    <select id=\"getEmp\" resultType=\"com.atguigu.mybatis.entity.Employee\">\n        select\n            <include refid=\"empColumn\"\/>\n        from `t_emp` where id = #{id}\n    <\/select><\/code><\/pre>\n\n\n\n
                                                          8.\u7279\u6b8a\u5b57\u7b26<\/h2>\n\n\n\n
                                                          \u2022\u4ee5\u540e\u5728xml\u4e2d\uff0c\u4ee5\u4e0b\u5b57\u7b26\u9700\u8981\u7528\u8f6c\u4e49\u5b57\u7b26\uff0c\u4e0d\u80fd\u76f4\u63a5\u5199<\/p>\n\n\n\n
                                                          \u539f\u59cb\u5b57\u7b26<\/strong><\/td>\u8f6c\u4e49\u5b57\u7b26<\/strong><\/td><\/tr>
                                                          &<\/td>&amp;<\/td><\/tr>
                                                          <<\/td>&lt;<\/td><\/tr>
                                                          ><\/td>&gt;<\/td><\/tr>
                                                          “<\/td>&quot;<\/td><\/tr>
                                                          ‘<\/td>&apos;<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
                                                          9.MyBais \u6269\u5c55<\/h2>\n\n\n\n
                                                          1.\u7f13\u5b58\u673a\u5236<\/h3>\n\n\n\n
                                                            \n
                                                          • MyBatis \u62e5\u6709\u4e8c\u7ea7\u7f13\u5b58\u673a\u5236\uff1a\n
                                                              \n
                                                            • \u4e00\u7ea7\u7f13\u5b58\u9ed8\u8ba4\u5f00\u542f\uff1b \u4e8b\u52a1\u7ea7\u522b\uff1a\u5f53\u524d\u4e8b\u52a1\u5171\u4eab<\/li>\n\n\n\n
                                                            • \u4e8c\u7ea7\u7f13\u5b58\u9700\u8981\u624b\u52a8\u914d\u7f6e\u5f00\u542f\uff1a\u6240\u6709\u4e8b\u52a1\u5171\u4eab<\/li>\n\n\n\n
                                                            • \u7f13\u5b58\u4e2d\u6709\u5c31\u4e0d\u7528\u67e5\u6570\u636e\u5e93\uff1b<\/li>\n\n\n\n
                                                            • L1~LN\uff1aN\u7ea7\u7f13\u5b58\n
                                                                \n
                                                              • \u6570\u5b57\u8d8a\u5c0f\u79bb\u6211\u8d8a\u8fd1\uff0c\u67e5\u7684\u8d8a\u5feb\u3002\u5b58\u50a8\u8d8a\u5c0f\uff0c\u9020\u4ef7\u8d8a\u9ad8\u3002<\/li>\n\n\n\n
                                                              • \u6570\u5b57\u8d8a\u5927\u79bb\u6211\u8d8a\u8fdc\uff0c\u67e5\u7684\u8d8a\u6162\u3002\u5b58\u50a8\u8d8a\u5927\uff0c\u9020\u4ef7\u8d8a\u4f4e\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                                                                \u4e00\u7ea7\u7f13\u5b58<\/h4>\n\n\n\n
                                                                  \n
                                                                • \u4f5c\u7528\u57df\uff1a\u4e00\u7ea7\u7f13\u5b58\u4e5f\u79f0\u4e3a\u4f1a\u8bdd\uff08SqlSession\uff09\u7ea7\u7f13\u5b58\uff0c\u5b83\u7684\u4f5c\u7528\u57df\u662f\u5355\u4e2a SqlSession\u3002\u5728\u540c\u4e00\u4e2a SqlSession \u4e2d\uff0c\u6267\u884c\u76f8\u540c\u7684 SQL \u67e5\u8be2\u65f6\uff0cMyBatis \u4f1a\u4f18\u5148\u4ece\u4e00\u7ea7\u7f13\u5b58\u4e2d\u83b7\u53d6\u6570\u636e\uff0c\u800c\u4e0d\u662f\u518d\u6b21\u67e5\u8be2\u6570\u636e\u5e93\u3002<\/li>\n\n\n\n
                                                                • \u539f\u7406\uff1a\u5f53\u4e00\u4e2a SqlSession \u6267\u884c\u67e5\u8be2\u64cd\u4f5c\u65f6\uff0cMyBatis \u4f1a\u5c06\u67e5\u8be2\u7ed3\u679c\u5b58\u50a8\u5728\u8be5 SqlSession \u7684\u7f13\u5b58\u4e2d\u3002\u5982\u679c\u540e\u7eed\u518d\u6b21\u6267\u884c\u76f8\u540c\u7684\u67e5\u8be2\uff08\u76f8\u540c\u7684 SQL \u8bed\u53e5\u548c\u53c2\u6570\uff09\uff0cMyBatis \u4f1a\u76f4\u63a5\u4ece\u7f13\u5b58\u4e2d\u8fd4\u56de\u7ed3\u679c\uff0c\u800c\u4e0d\u4f1a\u518d\u6b21\u8bbf\u95ee\u6570\u636e\u5e93\u3002<\/li>\n\n\n\n
                                                                • \u5931\u6548\u60c5\u51b5\uff1a\u5f53 SqlSession \u6267\u884c\u63d2\u5165\u3001\u66f4\u65b0\u3001\u5220\u9664\u64cd\u4f5c\uff0c\u6216\u8005\u8c03\u7528 SqlSession \u7684 clearCache() \u65b9\u6cd5\u65f6\uff0c\u4e00\u7ea7\u7f13\u5b58\u4f1a\u88ab\u6e05\u7a7a\u3002<\/li>\n<\/ul>\n\n\n\n
                                                                  \u793a\u4f8b\u4ee3\u7801:<\/p>\n\n\n\n
                                                                  try (SqlSession session = sqlSessionFactory.openSession()) {\n    UserMapper mapper = session.getMapper(UserMapper.class);\n    \/\/ \u7b2c\u4e00\u6b21\u67e5\u8be2\n    User user1 = mapper.getUserById(1); \n    \/\/ \u7b2c\u4e8c\u6b21\u67e5\u8be2\uff0c\u4f7f\u7528\u7f13\u5b58\n    User user2 = mapper.getUserById(1); \n    System.out.println(user1 == user2); \/\/ \u8f93\u51fa true\n}<\/code><\/pre>\n\n\n\n
                                                                  \u4e8c\u7ea7\u7f13\u5b58<\/h4>\n\n\n\n
                                                                    \n
                                                                  • \u4f5c\u7528\u57df\uff1a\u4e8c\u7ea7\u7f13\u5b58\u4e5f\u79f0\u4e3a\u547d\u540d\u7a7a\u95f4\uff08Mapper\uff09\u7ea7\u7f13\u5b58\uff0c\u5b83\u7684\u4f5c\u7528\u57df\u662f\u540c\u4e00\u4e2a\u547d\u540d\u7a7a\u95f4\uff08Mapper \u63a5\u53e3\uff09\u3002\u4e0d\u540c\u7684 SqlSession \u53ef\u4ee5\u5171\u4eab\u4e8c\u7ea7\u7f13\u5b58\u4e2d\u7684\u6570\u636e\uff0c\u53ea\u8981\u5b83\u4eec\u64cd\u4f5c\u7684\u662f\u540c\u4e00\u4e2a Mapper \u63a5\u53e3\u3002<\/li>\n\n\n\n
                                                                  • \u539f\u7406\uff1aMyBatis \u7684\u4e8c\u7ea7\u7f13\u5b58\u662f\u57fa\u4e8e Mapper \u547d\u540d\u7a7a\u95f4\u7684\uff0c\u6bcf\u4e2a Mapper \u90fd\u6709\u81ea\u5df1\u72ec\u7acb\u7684\u4e8c\u7ea7\u7f13\u5b58\u3002\u5f53\u4e00\u4e2a SqlSession \u6267\u884c\u67e5\u8be2\u64cd\u4f5c\u5e76\u5c06\u7ed3\u679c\u5b58\u50a8\u5728\u4e8c\u7ea7\u7f13\u5b58\u4e2d\u540e\uff0c\u5176\u4ed6 SqlSession \u6267\u884c\u76f8\u540c\u7684\u67e5\u8be2\u65f6\uff0c\u53ef\u4ee5\u76f4\u63a5\u4ece\u4e8c\u7ea7\u7f13\u5b58\u4e2d\u83b7\u53d6\u6570\u636e\u3002<\/li>\n\n\n\n
                                                                  • \u5f00\u542f\u65b9\u5f0f\uff1a\u8981\u5f00\u542f\u4e8c\u7ea7\u7f13\u5b58\uff0c\u9700\u8981\u5728 Mapper XML \u6587\u4ef6\u4e2d\u6dfb\u52a0 \u6807\u7b7e\uff0c\u6216\u8005\u5728 Mapper \u63a5\u53e3\u4e0a\u6dfb\u52a0 @CacheNamespace \u6ce8\u89e3\u3002<\/li>\n\n\n\n
                                                                  • \u5931\u6548\u60c5\u51b5\uff1a\u5f53 Mapper \u5bf9\u5e94\u7684 SqlSession \u6267\u884c\u63d2\u5165\u3001\u66f4\u65b0\u3001\u5220\u9664\u64cd\u4f5c\u65f6\uff0c\u8be5 Mapper \u7684\u4e8c\u7ea7\u7f13\u5b58\u4f1a\u88ab\u6e05\u7a7a\u3002<\/li>\n<\/ul>\n\n\n\n
                                                                    \u793a\u4f8b\u4ee3\u7801<\/p>\n\n\n\n
                                                                    <mapper namespace=\"com.example.mapper.UserMapper\">\n    <!-- \u5f00\u542f\u4e8c\u7ea7\u7f13\u5b58 -->\n    <cache \/> \n    <select id=\"getUserById\" resultType=\"com.example.entity.User\">\n        SELECT * FROM user WHERE id = #{id}\n    <\/select>\n<\/mapper><\/code><\/pre>\n\n\n\n
                                                                    try (SqlSession session1 = sqlSessionFactory.openSession();\n     SqlSession session2 = sqlSessionFactory.openSession()) {\n    UserMapper mapper1 = session1.getMapper(UserMapper.class);\n    UserMapper mapper2 = session2.getMapper(UserMapper.class);\n    \/\/ \u7b2c\u4e00\u6b21\u67e5\u8be2\uff0c\u5b58\u5165\u4e8c\u7ea7\u7f13\u5b58\n    User user1 = mapper1.getUserById(1); \n    \/\/ \u7b2c\u4e8c\u6b21\u67e5\u8be2\uff0c\u4ece\u4e8c\u7ea7\u7f13\u5b58\u83b7\u53d6\n    User user2 = mapper2.getUserById(1); \n    System.out.println(user1 == user2); \/\/ \u8f93\u51fa false\uff0c\u4f46\u6570\u636e\u5185\u5bb9\u76f8\u540c\n}<\/code><\/pre>\n\n\n\n
                                                                    \"\"<\/div><\/figure>\n\n\n\n
                                                                    \"\"<\/div><\/figure>\n\n\n\n
                                                                    2.\u63d2\u4ef6\u673a\u5236<\/h3>\n\n\n\n
                                                                      \n
                                                                    • MyBatis \u5e95\u5c42\u4f7f\u7528 \u62e6\u622a\u5668\u673a\u5236\u63d0\u4f9b\u63d2\u4ef6\u529f\u80fd\uff0c\u65b9\u4fbf\u7528\u6237\u5728SQL\u6267\u884c\u524d\u540e\u8fdb\u884c\u62e6\u622a\u589e\u5f3a\u3002<\/li>\n<\/ul>\n\n\n\n
                                                                      \"\"<\/div><\/figure>\n\n\n\n
                                                                        \n
                                                                      • \u62e6\u622a\u5668\uff1aInterceptor<\/li>\n\n\n\n
                                                                      • \u62e6\u622a\u5668\u53ef\u4ee5\u62e6\u622a \u56db\u5927\u5bf9\u8c61 \u7684\u6267\u884c\n
                                                                          \n
                                                                        • ParameterHandler\uff08\u53c2\u6570\u5904\u7406\u5668\uff09\uff1a\u5904\u7406SQL\u7684\u53c2\u6570\u5bf9\u8c61<\/li>\n\n\n\n
                                                                        • ResultSetHandler\uff08\u7ed3\u679c\u96c6\u5904\u7406\u5668\uff09\uff1a\u5904\u7406SQL\u7684\u8fd4\u56de\u7ed3\u679c\u96c6<\/li>\n\n\n\n
                                                                        • StatementHandler\uff08\u8bed\u53e5\u5904\u7406\u5668\uff09\uff1a\u6570\u636e\u5e93\u7684\u5904\u7406\u5bf9\u8c61\uff0c\u7528\u4e8e\u6267\u884cSQL\u8bed\u53e5<\/li>\n\n\n\n
                                                                        • Executor\uff08\u6267\u884c\u5668\uff09\uff1aMyBatis\u7684\u6267\u884c\u5668\uff0c\u7528\u4e8e\u6267\u884c\u589e\u5220\u6539\u67e5\u64cd\u4f5c<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                                                                          10.PageHelper<\/h2>\n\n\n\n
                                                                            \n
                                                                          • PageHelper \u662f\u53ef\u4ee5\u7528\u5728 MyBatis \u4e2d\u7684\u4e00\u4e2a\u5f3a\u5927\u7684\u5206\u9875\u63d2\u4ef6<\/li>\n\n\n\n
                                                                          • \u5206\u9875\u63d2\u4ef6\u5c31\u662f\u5229\u7528MyBatis \u63d2\u4ef6\u673a\u5236\uff0c\u5728\u5e95\u5c42\u7f16\u5199\u4e86 \u5206\u9875Interceptor\uff0c\u6bcf\u6b21SQL\u67e5\u8be2\u4e4b\u524d\u4f1a\u81ea\u52a8\u62fc\u88c5\u5206\u9875\u6570\u636e\n
                                                                              \n
                                                                            • select * from emp limit\u00a0 0,10<\/li>\n\n\n\n
                                                                            • \u5206\u9875\u91cd\u70b9\uff1a\n
                                                                                \n
                                                                              • \u524d\u7aef \u7b2c1\u9875\uff1a limit\u00a0 0,10<\/li>\n\n\n\n
                                                                              • \u524d\u7aef \u7b2c2\u9875\uff1a limit\u00a0 10,10<\/li>\n\n\n\n
                                                                              • \u524d\u7aef \u7b2c3\u9875\uff1a limit\u00a0 20,10<\/li>\n\n\n\n
                                                                              • \u524d\u7aef \u7b2cN\u9875\uff1alimit startIndex,pageSize<\/li>\n\n\n\n
                                                                              • \u8ba1\u7b97\u89c4\u5219\uff1a pageNum = 1\uff0c\u00a0 pageSize = 10<\/li>\n\n\n\n
                                                                              • startIndex = (pageNum – 1)*pageSize<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n
                                                                                \u5b98\u7f51:https:\/\/pagehelper.github.io<\/p>\n\n\n\n
                                                                                \u4f7f\u7528<\/h3>\n\n\n\n
                                                                                \u5728 pom.xml \u4e2d\u6dfb\u52a0\u5982\u4e0b\u4f9d\u8d56\uff1a<\/p>\n\n\n\n
                                                                                <dependency>\n    <groupId>com.github.pagehelper<\/groupId>\n    <artifactId>pagehelper<\/artifactId>\n    <version>\u6700\u65b0\u7248\u672c<\/version>\n<\/dependency><\/code><\/pre>\n\n\n\n
                                                                                \u914d\u7f6e\u62e6\u622a\u5668\u63d2\u4ef6<\/p>\n\n\n\n
                                                                                \n\n@MapperScan(\"com.atguigu.mybatis.mapper\") \/\/\u6279\u91cf\u53ea\u626b\u63cfmapper\n@Configuration\npublic class MyBatisConfig {\n\n    @Bean\n    PageInterceptor pageInterceptor(){\n        \/\/1\u3001\u521b\u5efa \u5206\u9875\u63d2\u4ef6 \u5bf9\u8c61\n        PageInterceptor interceptor = new PageInterceptor();\n        \/\/2\u3001\u8bbe\u7f6e \u53c2\u6570\n        \/\/.......\n        Properties properties = new Properties();\n        properties.setProperty(\"reasonable\", \"true\");\n\n        interceptor.setProperties(properties);\n        return interceptor;\n    }\n}<\/code><\/pre>\n\n\n\n
                                                                                \u6d4b\u8bd5\u7c7b<\/p>\n\n\n\n
                                                                                @SpringBootTest\npublic class PageTest {\n\n    @Autowired\n    EmpService empService;\n\n    @Test\n    void test02(){\n\n        \/\/\u540e\u7aef\u6536\u5230\u524d\u7aef\u4f20\u6765\u7684\u9875\u7801\n\n\n        \/\/\u54cd\u5e94\u524d\u7aef\u9700\u8981\u7684\u6570\u636e\uff1a\n        \/\/1\u3001\u603b\u9875\u7801\u3001\u603b\u8bb0\u5f55\u6570\n        \/\/2\u3001\u5f53\u524d\u9875\u7801\n        \/\/3\u3001\u672c\u9875\u6570\u636e\n        PageHelper.startPage(3,5);\n        \/\/ \u7d27\u8ddf\u7740 startPage \u4e4b\u540e \u7684\u65b9\u6cd5\u5c31\u4f1a\u6267\u884c\u7684 SQL \u5206\u9875\u67e5\u8be2\n        List<Emp> all = empService.getAll();\n        System.out.println(\"============\");\n\n        \/\/\u4ee5\u540e\u7ed9\u524d\u7aef\u8fd4\u56de\u5b83\n        PageInfo<Emp> info = new PageInfo<>(all);\n\n        \/\/\u5f53\u524d\u7b2c\u51e0\u9875\n        System.out.println(\"\u5f53\u524d\u9875\u7801\uff1a\"+info.getPageNum());\n        \/\/\u603b\u9875\u7801\n        System.out.println(\"\u603b\u9875\u7801\uff1a\"+info.getPages());\n        \/\/\u603b\u8bb0\u5f55\n        System.out.println(\"\u603b\u8bb0\u5f55\u6570\uff1a\"+info.getTotal());\n        \/\/\u6709\u6ca1\u6709\u4e0b\u4e00\u9875\n        System.out.println(\"\u6709\u6ca1\u6709\u4e0b\u4e00\u9875\uff1a\"+info.isHasNextPage());\n        \/\/\u6709\u6ca1\u6709\u4e0a\u4e00\u9875\n        System.out.println(\"\u6709\u6ca1\u6709\u4e0a\u4e00\u9875\uff1a\"+info.isHasPreviousPage());\n        \/\/\u672c\u9875\u6570\u636e\n        System.out.println(\"\u672c\u9875\u6570\u636e\uff1a\"+info.getList());\n\n    }\n\n    @Test\n    void test01(){\n\n        \/**\n         * \u539f\u7406\uff1a\u62e6\u622a\u5668\uff1b\n         * \u539f\u4e1a\u52a1\u5e95\u5c42\uff1aselect * from emp;\n         * \u62e6\u622a\u505a\u4e24\u4ef6\u4e8b\uff1a\n         * 1\uff09\u3001\u7edf\u8ba1\u8fd9\u4e2a\u8868\u7684\u603b\u6570\u91cf\n         * 2\uff09\u3001\u7ed9\u539f\u4e1a\u52a1\u5e95\u5c42SQL \u52a8\u6001\u62fc\u63a5\u4e0a limit 0,5;\n         *\n         * ThreadLocal\uff1a \u540c\u4e00\u4e2a\u7ebf\u7a0b\u5171\u4eab\u6570\u636e\n         *    1\u3001\u7b2c\u4e00\u4e2a\u67e5\u8be2\u4ece ThreadLocal \u4e2d\u83b7\u53d6\u5230\u5171\u4eab\u6570\u636e\uff0c\u6267\u884c\u5206\u9875\n         *    2\u3001\u7b2c\u4e00\u4e2a\u6267\u884c\u5b8c\u4f1a\u628a ThreadLocal \u5206\u9875\u6570\u636e\u5220\u9664\n         *    3\u3001\u4ee5\u540e\u7684\u67e5\u8be2\uff0c\u4ece ThreadLocal \u4e2d\u62ff\u4e0d\u5230\u5206\u9875\u6570\u636e\uff0c\u5c31\u4e0d\u4f1a\u5206\u9875\n         *\n         *\/\n        PageHelper.startPage(3,5);\n        \/\/ \u7d27\u8ddf\u7740 startPage \u4e4b\u540e \u7684\u65b9\u6cd5\u5c31\u4f1a\u6267\u884c\u7684 SQL \u5206\u9875\u67e5\u8be2\n        List<Emp> all = empService.getAll();\n        for (Emp emp : all) {\n            System.out.println(emp);\n        }\n\n        System.out.println(\"===============\");\n        List<Emp> all1 = empService.getAll();\n        System.out.println(all1.size());\n    }\n}<\/code><\/pre>\n\n\n\n
                                                                                    @GetMapping(\"\/emp\/page\")\n    public PageInfo getPage(@RequestParam(value = \"pageNum\",defaultValue = \"1\") Integer pageNum){\n        PageHelper.startPage(pageNum, 5);\n        List<Emp> all = empService.getAll();\n        return new PageInfo<>(all);\n    }<\/code><\/pre>\n\n\n\n
                                                                                MyBatis\u7bc7\u5b8c\u7ed3<\/h2>\n\n\n\n
                                                                                <\/p>\n","protected":false},"excerpt":{"rendered":"
                                                                                \u4e09.MyBatis\u7bc7 1.\u7b80\u4ecb MyBatis \u662f\u4e00\u4e2a\u534a\u81ea\u52a8\u5316\u7684 ORM\uff08\u5bf9\u8c61\u5173\u7cfb\u6620\u5c04\uff09\u6846\u67b6\uff0c\u5141\u8bb8\u5f00 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[17,7,1],"tags":[],"class_list":["post-7835","post","type-post","status-publish","format-standard","hentry","category-mybatis","category-ssm-springboot","category-learn"],"_links":{"self":[{"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/posts\/7835","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/comments?post=7835"}],"version-history":[{"count":21,"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/posts\/7835\/revisions"}],"predecessor-version":[{"id":7888,"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/posts\/7835\/revisions\/7888"}],"wp:attachment":[{"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/media?parent=7835"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/categories?post=7835"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.legendkiller.xyz\/index.php\/wp-json\/wp\/v2\/tags?post=7835"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}