2012-12-08 50 views
0

我使用MyBatis的,我遇到一个关联查询问题,请首先看看表结构。关联查询问题

DROP TABLE IF EXISTS `comp_items_spec`; 

CREATE TABLE `comp_items_spec` (
    `id` int(11) NOT NULL AUTO_INCREMENT, 
    `comp_id` int(11) NOT NULL, 
    `content_type_id` int(11) NOT NULL, 
    `in_list_flag` char(1) DEFAULT NULL, 
    `label` varchar(200) DEFAULT NULL, 
    `static_flag` char(1) DEFAULT NULL, 
    `ext1_name` varchar(200) DEFAULT NULL, 
    `ext1_value` text, 
    `ext2_name` varchar(200) DEFAULT NULL, 
    `ext2_value` text, 
    `ext3_name` varchar(200) DEFAULT NULL, 
    `ext3_value` text, 
    `ext4_name` varchar(200) DEFAULT NULL, 
    `ext4_value` text, 
    `ext5_name` varchar(200) DEFAULT NULL, 
    `ext5_value` text, 
    PRIMARY KEY (`id`) 
) ENGINE=InnoDB AUTO_INCREMENT=47 DEFAULT CHARSET=latin1; 

/*Data for the table `comp_items_spec` */ 

insert into `comp_items_spec`(`id`,`comp_id`,`content_type_id`,`in_list_flag`,`label`,`static_flag`,`ext1_name`,`ext1_value`,`ext2_name`,`ext2_value`,`ext3_name`,`ext3_value`,`ext4_name`,`ext4_value`,`ext5_name`,`ext5_value`) values (43,22,1,'\0','description','Y','description','description1......',NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL),(44,22,3,'\0','static image','Y',NULL,'http://img3.cache.netease.com/cnews/2012/12/6/20121206092637ba11c.jpg',NULL,'501',NULL,'425',NULL,NULL,NULL,NULL); 

/*Table structure for table `components_spec` */ 

DROP TABLE IF EXISTS `components_spec`; 

CREATE TABLE `components_spec` (
    `id` int(11) NOT NULL AUTO_INCREMENT, 
    `name` varchar(200) DEFAULT NULL, 
    `show_latest_num` int(11) DEFAULT NULL, 
    `more_link_url` varchar(200) DEFAULT NULL, 
    `more_link_flag` char(1) DEFAULT NULL, 
    `open_in_new_flag` char(1) DEFAULT NULL, 
    `create_date` datetime DEFAULT NULL, 
    `update_date` datetime DEFAULT NULL, 
    `creator_sso` varchar(20) DEFAULT NULL, 
    `updator_sso` varchar(20) DEFAULT NULL, 
    KEY `id` (`id`) 
) ENGINE=InnoDB AUTO_INCREMENT=23 DEFAULT CHARSET=latin1; 

/*Data for the table `components_spec` */ 

insert into `components_spec`(`id`,`name`,`show_latest_num`,`more_link_url`,`more_link_flag`,`open_in_new_flag`,`create_date`,`update_date`,`creator_sso`,`updator_sso`) values (22,'Banner',5,'more.blog.ge.com','Y','Y','2012-12-08 21:30:58','2012-12-08 21:30:58','502156886','502156886'); 

components_spec和comp_items_spec之间的关系是1:N,comp_items_spec有两种数据,动态项和其是从塔static_flag区分静态项的,它是动态的项目时static_flag =“N”,我也定义Bean ComponentSpec和CompItemSpec来映射实体。请从下面看源代码:

import java.util.ArrayList; 
import java.util.Date; 
import java.util.List; 

public class ComponentSpec { 
    private int id; 
    private String name; 
    private int showLatestNum; 
    private String moreLinkUrl; 
    private char moreLinkFlag; 
    private char openInNewFlag; 
    private Date createDate; 
    private Date updateDate; 
    private String creatorSSO; 
    private String updatorSSO; 
    private List<CompItemSpec> staticItemSpecList =new ArrayList<CompItemSpec>(); 
    private List<CompItemSpec> dynamicItemSpecList =new ArrayList<CompItemSpec>(); 

    public Date getCreateDate() { 
     return createDate; 
    } 

    public void setCreateDate(Date createDate) { 
     this.createDate = createDate; 
    } 

    public int getId() { 
     return id; 
    } 

    public void setId(int id) { 
     this.id = id; 
    } 

    public char getMoreLinkFlag() { 
     return moreLinkFlag; 
    } 

    public void setMoreLinkFlag(char moreLinkFlag) { 
     this.moreLinkFlag = moreLinkFlag; 
    } 

    public String getMoreLinkUrl() { 
     return moreLinkUrl; 
    } 

    public void setMoreLinkUrl(String moreLinkUrl) { 
     this.moreLinkUrl = moreLinkUrl; 
    } 

    public String getName() { 
     return name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    public int getShowLatestNum() { 
     return showLatestNum; 
    } 

    public void setShowLatestNum(int showLatestNum) { 
     this.showLatestNum = showLatestNum; 
    } 

    public Date getUpdateDate() { 
     return updateDate; 
    } 

    public void setUpdateDate(Date updateDate) { 
     this.updateDate = updateDate; 
    } 

    public char getOpenInNewFlag() { 
     return openInNewFlag; 
    } 

    public void setOpenInNewFlag(char openInNewFlag) { 
     this.openInNewFlag = openInNewFlag; 
    } 

    public List<CompItemSpec> getStaticItemSpecList() { 
     return staticItemSpecList; 
    } 

    public void addStaticItemSpec(CompItemSpec compStaticItemSpec){ 
     getStaticItemSpecList().add(compStaticItemSpec); 
     compStaticItemSpec.setComponentSpec(this); 
    } 

    public List<CompItemSpec> getDynamicItemSpecList() { 
     return dynamicItemSpecList; 
    } 

    public void addDynamicItemSpec(CompItemSpec dynamicItemSpec){ 
     getDynamicItemSpecList().add(dynamicItemSpec); 
     dynamicItemSpec.setComponentSpec(this); 
    } 

    public String getCreatorSSO() { 
     return creatorSSO; 
    } 

    public void setCreatorSSO(String creatorSSO) { 
     this.creatorSSO = creatorSSO; 
    } 

    public String getUpdatorSSO() { 
     return updatorSSO; 
    } 

    public void setUpdatorSSO(String updatorSSO) { 
     this.updatorSSO = updatorSSO; 
    } 


} 

public class CompItemSpec { 
    private int id; 
    private int compId; 
    private int contentTypeId; 
    private char inListFlag; 
    private char staticFlag; 
    private String label; 
    private String ext1Name; 
    private String ext1Value; 
    private String ext2Name; 
    private String ext2Value; 
    private String ext3Name; 
    private String ext3Value; 
    private String ext4Name; 
    private String ext4Value; 
    private String ext5Name; 
    private String ext5Value; 
    private ComponentSpec componentSpec; 

    public int getCompId() { 
     return compId; 
    } 

    public void setCompId(int compId) { 
     this.compId = compId; 
    } 

    public String getExt1Name() { 
     return ext1Name; 
    } 

    public void setExt1Name(String ext1Name) { 
     this.ext1Name = ext1Name; 
    } 

    public String getExt1Value() { 
     return ext1Value; 
    } 

    public void setExt1Value(String ext1Value) { 
     this.ext1Value = ext1Value; 
    } 

    public String getExt2Name() { 
     return ext2Name; 
    } 

    public void setExt2Name(String ext2Name) { 
     this.ext2Name = ext2Name; 
    } 

    public String getExt2Value() { 
     return ext2Value; 
    } 

    public void setExt2Value(String ext2Value) { 
     this.ext2Value = ext2Value; 
    } 

    public String getExt3Name() { 
     return ext3Name; 
    } 

    public void setExt3Name(String ext3Name) { 
     this.ext3Name = ext3Name; 
    } 

    public String getExt3Value() { 
     return ext3Value; 
    } 

    public void setExt3Value(String ext3Value) { 
     this.ext3Value = ext3Value; 
    } 

    public String getExt4Name() { 
     return ext4Name; 
    } 

    public void setExt4Name(String ext4Name) { 
     this.ext4Name = ext4Name; 
    } 

    public String getExt4Value() { 
     return ext4Value; 
    } 

    public void setExt4Value(String ext4Value) { 
     this.ext4Value = ext4Value; 
    } 

    public String getExt5Name() { 
     return ext5Name; 
    } 

    public void setExt5Name(String ext5Name) { 
     this.ext5Name = ext5Name; 
    } 

    public String getExt5Value() { 
     return ext5Value; 
    } 

    public void setExt5Value(String ext5Value) { 
     this.ext5Value = ext5Value; 
    } 

    public int getId() { 
     return id; 
    } 

    public void setId(int id) { 
     this.id = id; 
    } 

    public int getContentTypeId() { 
     return contentTypeId; 
    } 

    public void setContentTypeId(int contentTypeId) { 
     this.contentTypeId = contentTypeId; 
    } 

    public char getInListFlag() { 
     return inListFlag; 
    } 

    public void setInListFlag(char inListFlag) { 
     this.inListFlag = inListFlag; 
    } 

    public char getStaticFlag() { 
     return staticFlag; 
    } 

    public void setStaticFlag(char staticFlag) { 
     this.staticFlag = staticFlag; 
    } 

    public String getLabel() { 
     return label; 
    } 

    public void setLabel(String label) { 
     this.label = label; 
    } 

    public ComponentSpec getComponentSpec() { 
     return componentSpec; 
    } 

    public void setComponentSpec(ComponentSpec componentSpec) { 
     this.componentSpec = componentSpec; 
    } 
} 

的SqlMap是象下面这样:

<mapper namespace="com.ge.dao.ComponentSpecMapper"> 
<resultMap id="componentMap" type="componentSpec"> 
    <id column="id" property="id"/> 
    <result column="temp_id" property="tempId"/> 
    <result column="show_latest_num" property="showLatestNum"/> 
    <result column="more_link_url" property="moreLinkUrl"/> 
    <result column="more_link_flag" property="moreLinkFlag"/> 
    <result column="open_in_new_flag" property="openInNewFlag"/> 
    <result column="update_date" property="updateDate"/> 
    <result column="create_date" property="createDate"/> 
    <result column="updator_sso" property="updatorSSO"/> 
    <result column="creator_sso" property="creatorSSO"/> 
    <collection property="staticItemSpecList" ofType="itemSpec"> 
     <id column="static_item_id" property="id"/> 
     <result column="id" property="compId"/> 
     <result column="static_content_type_id" property="contentTypeId"/> 
     <result column="static_label" property="label"/> 
     <result column="static_ext1_value" property="ext1Value"/> 
     <result column="static_ext2_value" property="ext2Value"/> 
     <result column="static_ext3_value" property="ext3Value"/> 
     <result column="static_ext4_value" property="ext4Value"/> 
     <result column="static_ext5_value" property="ext5Value"/> 
    </collection> 
    <collection property="dynamicItemSpecList" ofType="itemSpec"> 
     <id column="dynamic_item_id" property="id"/> 
     <result column="id" property="compId"/> 
     <result column="dynamic_content_type_id" property="contentTypeId"/> 
     <result column="dynamic_in_list_flag" property="inListFlag"/> 
     <result column="dynamic_label" property="label"/> 
     <result column="dynamic_ext1_value" property="ext1Value"/> 
     <result column="dynamic_ext2_value" property="ext2Value"/> 
     <result column="dynamic_ext3_value" property="ext3Value"/> 
     <result column="dynamic_ext4_value" property="ext4Value"/> 
     <result column="dynamic_ext5_value" property="ext5Value"/> 
    </collection> 

</resultMap> 

<sql id="compSpecMain"> 
     SELECT 
      comp.id, 
      comp.name, 
      show_latest_num, 
      more_link_url, 
      more_link_flag, 
      open_in_new_flag, 
      create_date, 
      update_date, 
      creator_sso, 
      updator_sso, 
      si.id static_item_id, 
      si.content_type_id static_content_type_id, 
      si.in_list_flag static_in_list_flag, 
      si.label static_label, 
      si.ext1_value static_ext1_value, 
      si.ext2_value static_ext2_value, 
      si.ext3_value static_ext3_value, 
      si.ext4_value static_ext4_value, 
      si.ext5_value static_ext5_value, 
      di.id dynamic_item_id, 
      di.content_type_id dynamic_content_type_id, 
      di.in_list_flag dynamic_in_list_flag, 
      di.label dynamic_label, 
      di.ext1_value dynamic_ext1_value, 
      di.ext2_value dynamic_ext2_value, 
      di.ext3_value dynamic_ext3_value, 
      di.ext4_value dynamic_ext4_value, 
      di.ext5_value dynamic_ext5_value 
     FROM components_spec comp 
      LEFT JOIN comp_items_spec si ON si.comp_id=comp.id AND si.static_flag='Y' 
      LEFT JOIN comp_items_spec di ON di.comp_id=comp.id AND di.static_flag='N' 
</sql> 

<select id="selectComponentSpecByID" parameterType="int" resultMap="componentMap"> 
     <include refid="compSpecMain"/> 
     WHERE 
      comp.id=#{id} 
</select> 

<select id="selectComponentSpecByName" parameterType="string" resultMap="componentMap"> 
     <include refid="compSpecMain"/> 
     WHERE 
      comp.name like #{name} 

</select> 

这里的问题是,当我做selectComponentSpecByID查询,动态项目列表应该是没有什么但实际的结果是两个要素,我认为这是与结果地图定义的问题,但没有胶水。有什么建议么?谢谢 。

回答

1

终于让我找到了解决办法我自己,因为当id属性为null,这意味着没有在结果检索到的记录,MyBatis的还是对它们进行比较,并把它们作为有效的结果,并把它们放到子列表中,这就是原因,修复它,只需定义不收集元素的notNullColumn防止null id。完成!

<resultMap id="componentMap" type="componentSpec"> 
     <id column="id" property="id"/> 
     <result column="temp_id" property="tempId"/> 
     <result column="show_latest_num" property="showLatestNum"/> 
     <result column="more_link_url" property="moreLinkUrl"/> 
     <result column="more_link_flag" property="moreLinkFlag"/> 
     <result column="open_in_new_flag" property="openInNewFlag"/> 
     <result column="update_date" property="updateDate"/> 
     <result column="create_date" property="createDate"/> 
     <result column="updator_sso" property="updatorSSO"/> 
     <result column="creator_sso" property="creatorSSO"/> 
     <collection property="staticItemSpecList" notNullColumn="static_item_id" ofType="itemSpec"> 
      <id column="static_item_id" property="id"/> 
      <result column="id" property="compId"/> 
      <result column="static_content_type_id" property="contentTypeId"/> 
      <result column="static_label" property="label"/> 
      <result column="static_ext1_value" property="ext1Value"/> 
      <result column="static_ext2_value" property="ext2Value"/> 
      <result column="static_ext3_value" property="ext3Value"/> 
      <result column="static_ext4_value" property="ext4Value"/> 
      <result column="static_ext5_value" property="ext5Value"/> 
     </collection> 
     <collection property="dynamicItemSpecList" notNullColumn="dynamic_item_id" ofType="itemSpec"> 
      <id column="dynamic_item_id" property="id"/> 
      <result column="id" property="compId"/> 
      <result column="dynamic_content_type_id" property="contentTypeId"/> 
      <result column="dynamic_in_list_flag" property="inListFlag"/> 
      <result column="dynamic_label" property="label"/> 
      <result column="dynamic_ext1_value" property="ext1Value"/> 
      <result column="dynamic_ext2_value" property="ext2Value"/> 
      <result column="dynamic_ext3_value" property="ext3Value"/> 
      <result column="dynamic_ext4_value" property="ext4Value"/> 
      <result column="dynamic_ext5_value" property="ext5Value"/> 
     </collection> 

    </resultMap>