SQL复杂拼接

一、MySql

1.单引号嵌双引号

select CONCAT("'%",'"',"dengji",'"',"%'") from dual;结果输出：'%"dengji"%'  这里的%只是做模糊查询用没有其它含义

2.双引号嵌单引号

select CONCAT('"%',"'","b","'",'%"') from dual;结果输出："%'b'%"这里的%只是做模糊查询用没有其它含义

3.如上拼接实际运用于mybatis

<select id="getSupplementInfo" resultType="cn.tongdun.model.entity.supplement.SupplementDO">
        select id,typeName,jsonStr,create_time as createTime,modify_time as modifyTime from river_supplement_info
        where 1=1
        <if test="typeName != null">and typeName=#{typeName}</if>
        <if test="key != null and searchField!=null">and jsonStr like CONCAT('%','"',#{searchField},'"',":",'"',#{key},'"','%')</if>
        order by create_time DESC
</select>

二、Oracle

待补充