如何重用带有参数的SQL片段? [英] How can I reuse an SQL fragment with parameters?

问题描述

我打算制作一个片段以供参数重用.

I'm intending to make a fragment for reusing with parameters.

<insert ...>
  <selectKey keyProperty="id" resultType="_long" order="BEFORE">
    <choose>
      <when test="_databaseId == 'derby'">
        VALUES NEXT VALUE FOR SOME_ID_SEQ
      </when>
      <otherwise>
        SELECT SOME_ID_SEQ.NEXTVAL FROM DUAL
      </otherwise>
    </choose>
  </selectKey>
  INSERT INTO ...
</insert>

我可以使用参数制作一个SQL片段吗?

Can I make an SQL fragment using parameters?

<sql id="selectKeyFromSequence">
  <selectKey keyProperty="id" resultType="_long" order="BEFORE">
    <choose>
      <when test="_databaseId == 'derby'">
        VALUES NEXT VALUE FOR #{sequenceName}
      </when>
      <otherwise>
        SELECT #{sequenceName}.NEXTVAL FROM DUAL
      </otherwise>
    </choose>
  </selectKey>
</sql>

以便我可以像这样重用它们?

So that I can reuse them like this?

<insert ...>
  <include refid="...selectKeyFromSequence"/> <!-- How can I pass a parameter? -->
  INSERT INTO ...
</insert>

这可能吗?

推荐答案

从3.3.0版开始，您可以像这样进行操作:

As of version 3.3.0 you can do it like this:

<sql id="myinclude">
  from ${myproperty}
</sql>

<include refid="myinclude">
  <property name="myproperty" value="tablename"/>
</include>

请参见 http://www.mybatis.org/mybatis-3/sqlmap-xml中的SQL部分.html

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