动态 SQL ——之—— bind

bind 元素可以从 OGNL 表达式中创建一个变量并将其绑定到上下文

此博文 <深入了解MyBatis参数，深入了解mybatis> 解释的相当到位，谢谢博主；

另外博主的博客写的也是很好的。有机会多多进去学习 博文地址

 

此博文 《关于mybatis like》，作者在提供了解决方案（我没有遇到过）。

SELECT * FROM TNotific
<where>
	<if test="method != null">
		<bind name="pattern" value="'%' + method + '%'"/>
		and Method like #{pattern}
	</if>
	<if test="statusOfread != null">
		and StatusOfread = #{statusOfread,jdbcType=VARCHAR}
	</if>
	<if test="bizCaseId != null">
		and BizCaseId = #{bizCaseId,jdbcType=VARCHAR}
	</if>
</where>

入参

String statusOfread = "0";    String method = "U";   String bizCaseId = null;

执行SQL

SELECT * FROM TNotific WHERE Method like ? and StatusOfread = ? 
==> Parameters: %U%(String), 0(String)

---

---

SELECT * FROM TNotific 
<where>
	<if test="tNotific.method != null">
		<bind name="pattern" value="'%' + tNotification.method + '%'"/>
		and Method like #{pattern}
	</if>
	<if test="tNotific.statusOfRead != null">
		and StatusOfread = #{tNotific.statusOfRead,jdbcType=VARCHAR}
	</if>
	<if test="tNotification.bizCaseId != null">
		and BizCaseId = #{tNotific.bizCaseId,jdbcType=VARCHAR}
	</if>
</where>

入参

TNotific tNotific = new TNotific();
	tNotific.setMethod("U");
	tNotific.setStatusOfRead("0");
	tNotific.setBizCaseId("10000000012028");

SQL 执行结果

SELECT * FROM TNotific WHERE Method like ? and StatusOfread = ? and BizCaseId = ? 
==> Parameters: %U%(String), 0(String), 10000000012028(String)