實例說明ibatis動態查詢
最近做了很多動態的查詢,尤其是排序,以及一些狀態字段,所以就做了一個總的動態查詢,以不變應萬變,呵呵
ibatis動態查詢里面的sql代碼:
ibatis動態查詢Xml代碼：
<select id="getTopics" resultClass="topic" parameterClass="map">
<![CDATA[
select * from p_Topic
]]>
<dynamic prepend=" WHERE ">
<isPropertyAvailable property="authorId">
<isNotNull property="authorId" prepend=" and ">
authorId=#authorId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketId">
<isNotNull property="marketId" prepend=" and ">
marketId=#marketId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isDelete">
<isNotNull property="isDelete" prepend=" and ">
isDelete=#isDelete#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isBest">
<isNotNull property="isBest" prepend=" and ">
isBest=#isBest#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="statusStr">
<isNotNull property="statusStr" prepend=" and ">
$statusStr$
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketIdList">
<isNotNull property="marketIdList" prepend=" and marketId in ">
<iterate property="marketIdList" conjunction="," close=")" open="(">
#marketIdList[]#
</iterate>
</isNotNull>
</isPropertyAvailable>
</dynamic>
<dynamic prepend=" order by ">
<isPropertyAvailable property="orderStr">
<isNotNull property="orderStr">
$orderStr$
</isNotNull>
</isPropertyAvailable>
</dynamic>
<dynamic>
<isPropertyAvailable property="begin">
<isNotNull property="begin">
limit #begin#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="max" prepend=" , ">
<isNotNull property="max">
#max#
</isNotNull>
</isPropertyAvailable>
</dynamic>
</select>
<select id="getTopicCount" resultClass="java.lang.Long"
parameterClass="map">
<![CDATA[
select count(id) from p_Topic
]]>
<dynamic prepend=" WHERE ">
<isPropertyAvailable property="authorId">
<isNotNull property="authorId" prepend=" and ">
authorId=#authorId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketId">
<isNotNull property="marketId" prepend=" and ">
marketId=#marketId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isDelete">
<isNotNull property="isDelete" prepend=" and ">
isDelete=#isDelete#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isBest">
<isNotNull property="isBest" prepend=" and ">
isBest=#isBest#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="statusStr">
<isNotNull property="statusStr" prepend=" and ">
$statusStr$
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketIdList">
<isNotNull property="marketIdList" prepend=" and marketId in ">
<iterate property="marketIdList" conjunction="," close=")" open="(">
#marketIdList[]#
</iterate>
</isNotNull>
</isPropertyAvailable>
</dynamic>
</select>
ibatis動態查詢Xml代碼：
<select id="getTopics" resultClass="topic" parameterClass="map">
<![CDATA[
select * from p_Topic
]]>
<dynamic prepend=" WHERE ">
<isPropertyAvailable property="authorId">
<isNotNull property="authorId" prepend=" and ">
authorId=#authorId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketId">
<isNotNull property="marketId" prepend=" and ">
marketId=#marketId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isDelete">
<isNotNull property="isDelete" prepend=" and ">
isDelete=#isDelete#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isBest">
<isNotNull property="isBest" prepend=" and ">
isBest=#isBest#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="statusStr">
<isNotNull property="statusStr" prepend=" and ">
$statusStr$
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketIdList">
<isNotNull property="marketIdList" prepend=" and marketId in ">
<iterate property="marketIdList" conjunction="," close=")" open="(">
#marketIdList[]#
</iterate>
</isNotNull>
</isPropertyAvailable>
</dynamic>
<dynamic prepend=" order by ">
<isPropertyAvailable property="orderStr">
<isNotNull property="orderStr">
$orderStr$
</isNotNull>
</isPropertyAvailable>
</dynamic>
<dynamic>
<isPropertyAvailable property="begin">
<isNotNull property="begin">
limit #begin#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="max" prepend=" , ">
<isNotNull property="max">
#max#
</isNotNull>
</isPropertyAvailable>
</dynamic>
</select>
<select id="getTopicCount" resultClass="java.lang.Long"
parameterClass="map">
<![CDATA[
select count(id) from p_Topic
]]>
<dynamic prepend=" WHERE ">
<isPropertyAvailable property="authorId">
<isNotNull property="authorId" prepend=" and ">
authorId=#authorId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketId">
<isNotNull property="marketId" prepend=" and ">
marketId=#marketId#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isDelete">
<isNotNull property="isDelete" prepend=" and ">
isDelete=#isDelete#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="isBest">
<isNotNull property="isBest" prepend=" and ">
isBest=#isBest#
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="statusStr">
<isNotNull property="statusStr" prepend=" and ">
$statusStr$
</isNotNull>
</isPropertyAvailable>
<isPropertyAvailable property="marketIdList">
<isNotNull property="marketIdList" prepend=" and marketId in ">
<iterate property="marketIdList" conjunction="," close=")" open="(">
#marketIdList[]#
</iterate>
</isNotNull>
</isPropertyAvailable>
</dynamic>
</select>
這里需要注意的是:
#xxx# 代表xxx是屬性值,map里面的key或者是你的pojo對象里面的屬性,ibatis會自動在它的外面加上引號,表現在sql語句是這樣的 where xxx = 'xxx' ;而$xxxx$ 則是把xxxx作為字符串拼接到你的sql語句中,比如 order by topicId , 如果你不用$來拼接而用#的話,外面就會被加上引號的哦 比如你的語句這樣寫 ... order by #xxx# (xxx就是你傳進來的字符串topicId),ibatis 就會把他翻譯成 order by 'topicId' 這樣就報錯了，用$的結果就是這樣 order by topicId。
另外在ibatis動態查詢里要注意它的iterate。
Java代碼
<isPropertyAvailable property="marketIdList"> 注意 iterate 的property屬性 ,雖然你上面的isNotNull什么的都有這句,但這里一定要寫清楚,否則ibatis會找不到你的list的，ibatis動態查詢自然無法實現。 ibatis動態查詢中的數據訪問層代碼: Java代碼 public List ibatis動態查詢中的服務層代碼: Java代碼 public List Java代碼 public List Java代碼 public class Topic extends BaseObject implements Serializable { Java代碼 public class Topic extends BaseObject implements Serializable { ibatis動態查詢中的Pagination代碼: Java代碼： public class Pagination { 雖然代碼量有些大，但是這是一個總的ibatis動態查詢實例，您在實際工作中遇到相應的ibatis動態查詢問題可以參考一下。 【編輯推薦】
<isNotNull property="marketIdList" prepend=" and marketId in ">
<iterate property="marketIdList" conjunction="," close=")" open="(">
#marketIdList[]#
</iterate>
</isNotNull>
</isPropertyAvailable>
return getSqlMapClientTemplate().queryForList("getTopics", map);
}
Integer orderby, Integer status, Pagination pagination) {
Map
map.put("authorId", authorId);
map.put("isDelete", false);
map.put("marketIdList", marketIdList);
map.put("orderStr", "這里你組裝你的order字符串");
map.put("statusStr","這里你組裝你的status字符串");
map.put("begin", pagination.getOffset());
map.put("max", pagination.getPageSize());
//這個getTopicCount()方法和getTopics()大體是一致的,所以我的dao里面省略了它
Long total = topicDao.getTopicCount(map);
if (total == 0) {
return new ArrayList
} else {
pagination.setTotal(total);
List
return res;
}
}
Integer orderby, Integer status, Pagination pagination) {
Map
map.put("authorId", authorId);
map.put("isDelete", false);
map.put("marketIdList", marketIdList);
map.put("orderStr", "這里你組裝你的order字符串");
map.put("statusStr","這里你組裝你的status字符串");
map.put("begin", pagination.getOffset());
map.put("max", pagination.getPageSize());
//這個getTopicCount()方法和getTopics()大體是一致的,所以我的dao里面省略了它
Long total = topicDao.getTopicCount(map);
if (total == 0) {
return new ArrayList
} else {
pagination.setTotal(total);
List
return res;
}
}
/**
*
*/
private static final long serialVersionUID = -851973667810710701L;
private Long id;
private Long authorId;
private String authorName;
private Long marketId;
private String title;
private String tags;
private String content;
private Date pubdate;
private Integer isBest;
private Integer status;
private Integer isDelete;
private Integer clickCount;
private Integer replyCount;
private Date lastReplyTime;
//getter and setter 省略...
}
/**
*
*/
private static final long serialVersionUID = -851973667810710701L;
private Long id;
private Long authorId;
private String authorName;
private Long marketId;
private String title;
private String tags;
private String content;
private Date pubdate;
private Integer isBest;
private Integer status;
private Integer isDelete;
private Integer clickCount;
private Integer replyCount;
private Date lastReplyTime;
//getter and setter 省略...
}
/**
* 要查看的頁碼
*/
private int page;
/**
* 每頁顯示數
*/
private int pageSize;
/**
* 一共有多少頁
*/
private int totalPage;
/**
* 一共有多少條記錄
*/
private long total;
/**
* 當前頁的記錄數
*/
private int size;
/**
* 只需要topxx，不需要頁數信息了
*/
private boolean topOnly;
/**
*從第幾條記錄開始
*/
private int offset;
public void setOffset(int offset) {
this.offset = offset;
}
public Pagination(int page, int pageSize) {
this.page = page;
this.pageSize = pageSize;
}
public Pagination() {
}
public boolean require() {
return pageSize > 0 ? true : false;
}
public int from() {
return page * pageSize;
}
public int to() {
return from() + size;
}
public int getPage() {
return page;
}
public void setPage(int page) {
this.page = page;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public int getTotalPage() {
return totalPage;
}
public void setTotalPage(int totalPage) {
this.totalPage = totalPage;
}
public long getTotal() {
return total;
}
public void setTotal(long total) {
this.total = total;
if (pageSize > 0) {
this.totalPage = (int) Math.ceil(total / (double) pageSize);
} else {
this.totalPage = 1;
}
if (page >= totalPage) {
page = totalPage - 1;
}
if (page < 0)
page = 0;
if (pageSize > 0) {
if (page < totalPage - 1)
this.size = pageSize;
else
this.size = (int) (total % pageSize);
} else
