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if 动态标签：判断参数时满足test指定的条件，如果满足，就执行if（增加if标签中的SQL语句）;
注意：test里面使用的参数，可以是mybatis的默认参数，也可以是实体属性名，但是不能是没有指定别名的参数名(尤其是单个参数，也必须起别名，否则异常);
1.1 SQL
单独使用if，如果不满足条件会SQL拼接出问题，一般我门都跟where一起使用；
!-- List Anime selectAnimesByConditionUserIf(@Param("cid") Integer cid,@Param("author") String author); --
select id="selectAnimesByConditionUserIf" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
where `create_date` now()
if test="cid != null and cid != 0 "
cid = #{cid}
/if
if test="author != null"
and author like concat(%,#{author},%)
/if
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` where `create_date` now() and author like concat(%,?,%)
1.2 测试
@Test
public void testMybatisMapperDynamicSQlUserIf() throws IOException {
SqlSession defaultSqlSession = getSqlSessionFactory().openSession(true);
//获取mapper接口的代理实现类对象
AnimeMapper animeMapper = defaultSqlSession.getMapper(AnimeMapper.class);
//执行动态SQL，查询动漫列表
List Anime animeList = animeMapper.selectAnimesByConditionUserIf(0, "土豆");
animeList.forEach(System.out::println);
2、where + if
where if 动态标签组合：当where标签中，有if条件成立时，自动增加where关键字，如果所有的if都不成立，也不会多增加where关键字；
当where标签中，if成立，增加的SQL语句，前面多出现一个and或者 or关键字，会被自动过滤(剔除),但是末尾出现的，不会被剔除；
where标签中，也可以增加固定条件，再实际开发过程中，建议where标签中，必须写固定条件，不能全部写if判断；
2.1 SQL
!-- List Anime selectAnimesByConditionUserIfWhere(@Param("cid") Integer cid,@Param("author") String author); --
select id="selectAnimesByConditionUserIfWhere" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
where
if test="cid != null and cid != 0 "
and cid = #{cid}
/if
if test="author != null"
and author like concat(%,#{author},%)
/if
/where
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE author like concat(%,?,%)
2.2 测试
@Test
public void testMybatisMapperDynamicSQlUserIfWhere() throws IOException {
SqlSession defaultSqlSession = getSqlSessionFactory().openSession(true);
//获取mapper接口的代理实现类对象
AnimeMapper animeMapper = defaultSqlSession.getMapper(AnimeMapper.class);
//执行动态SQL，查询动漫列表
List Anime animeList = animeMapper.selectAnimesByConditionUserIfWhere(0, "土豆");
animeList.forEach(System.out::println);
3、trim + if
trim + if :可以实现动态SQL的定制操作，比如：where标签无法屏蔽末尾多出来的and或者or关键字，前缀 和后缀增加的内容，只有标签中的if标签成立，(需要增加条件，才拼接where)；
prefix:增加前缀固定字符串；
prefixOverrides：前缀覆盖(自动剔除指定的关键字)；
suffix：增加后缀固定字符串；
suffixOverrides：后缀覆盖(自动剔除指定的关键字)；
3.1 SQL
"and or" 中间一般都会添加一个空格；
!-- List Anime selectAnimesByConditionUserIfTrim(@Param("cid") Integer cid,@Param("author") String author); --
select id="selectAnimesByConditionUserIfTrim" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
trim prefix=" where " prefixOverrides="and or" suffixOverrides="and or" suffix=";"
if test="cid != null and cid != 0 "
cid = #{cid} and
/if
if test="author != null"
author like concat(%,#{author},%) and
/if
/trim
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` where author like concat(%,?,%) ;
3.2 测试
@Test
public void testMybatisMapperDynamicSQlUserIfTerm() throws IOException {
SqlSession defaultSqlSession = getSqlSessionFactory().openSession(true);
//获取mapper接口的代理实现类对象
AnimeMapper animeMapper = defaultSqlSession.getMapper(AnimeMapper.class);
//执行动态SQL，查询动漫列表
List Anime animeList = animeMapper.selectAnimesByConditionUserIfTrim(0, "土豆");
animeList.forEach(System.out::println);
4、set + if update
4.1SQL
!-- int updateAnimeByConditionUserIfSet(Anime animeFOrm); --
update id="updateAnimeByConditionUserIfSet"
update `animes`
set
if test="cid != null" `cid` = #{cid}, /if
if test="name != null" `name` = #{name}, /if
if test="author != null" `author` = #{author}, /if
if test="actor != null" `actor` = #{actor}, /if
if test="produce != null" `produce` = #{produce}, /if
if test="createDate != null" `create_date` = #{createDate}, /if
/set
where `id` = #{id}
/update
执行SQL:
Preparing: update `animes` SET `name` = ?, `author` = ? where `id` = ?
4.2 测试
@Test
public void testMybatisMapperDynamicSQlIfSetUpd() throws IOException {
SqlSession defaultSqlSession = getSqlSessionFactory().openSession(true);
//获取mapper接口的代理实现类对象
AnimeMapper animeMapper = defaultSqlSession.getMapper(AnimeMapper.class);
//模拟前端提供更新参数，实现动态更新，给说明值，就更新什么指端
Anime animeForm = new Anime();
animeForm.setId(637);
animeForm.setName("武动乾坤KGC");
animeForm.setAuthor("土豆KGC");
int row = animeMapper.updateAnimeByConditionUserIfSet(animeForm);
System.out.println(row);
5、trim + if update
5.1 SQL
!-- int updateAnimeByConditionUserIfTrim(Anime animeFOrm); --
update id="updateAnimeByConditionUserIfTrim"
trim prefix="update `animes` set " prefixOverrides="," suffixOverrides=","
if test="cid != null" `cid` = #{cid}, /if
if test="name != null" `name` = #{name}, /if
if test="author != null" `author` = #{author}, /if
if test="actor != null" `actor` = #{actor}, /if
if test="produce != null" `produce` = #{produce}, /if
if test="createDate != null" `create_date` = #{createDate}, /if
/trim
where `id` = #{id}
/update
执行SQL:
Preparing: update `animes` set `name` = ?, `author` = ? where `id` = ?
5.2 测试
@Test
public void testMybatisMapperDynamicSQlIfTrimUpd() throws IOException {
SqlSession defaultSqlSession = getSqlSessionFactory().openSession(true);
//获取mapper接口的代理实现类对象
AnimeMapper animeMapper = defaultSqlSession.getMapper(AnimeMapper.class);
//模拟前端提供更新参数，实现动态更新，给说明值，就更新什么指端
Anime animeForm = new Anime();
animeForm.setId(637);
animeForm.setName("武动乾坤22KGC");
animeForm.setAuthor("土豆22KGC");
int row = animeMapper.updateAnimeByConditionUserIfTrim(animeForm);
System.out.println(row);
6、where + choose + when (判断条件测试)
这个场景主要在传过来的参数，与放进SQL中的参数不一致的时候使用；
比如，前端传过来男/女,但是数据库中查询的时候需要使用1/2;(当然参数也可以在前端或者业务层处理好再放进SQL)
6.1 单引号与双引号的区别
6.1.1 test=cid != null and cid == "1"
test整体用单引号，里面的判断条件双引号；
!--List Anime selectAnimesByConditionUserChooseWhenOtherwise(@Param("cid") String cid); --
select id="selectAnimesByConditionUserChooseWhenOtherwise" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
where
choose
!-- test整体使用单引号,判断条件使用双引号 --
when test=cid != null and cid == "1"
and cid = 1
/when
when test=cid != null and cid == "2"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
/where
/select
6.1.1 测试
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.1.2 test="cid != null and cid == 1"
test整体用双引号，里面的判断条件单引号；
...
choose
!-- test整体使用双引号,判断条件使用单引号 --
when test="cid != null and cid == 1"
and cid = 1
/when
when test="cid != null and cid == 2"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
6.1.2 测试
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL：
-- SQL没有报错，但是 cid == 2 的条件没有成立，而是走了默认参数 cid = 3
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 3
-- 可以查到数据，但是数据不正确，是cid=3的数据
Anime(id=301, cid=3, name=完美世界, author=辰东, actor=石昊, produce=玄机科技, createDate=Tue Apr 05 00:00:00 CST 2022)
6.1.3 "cid != null and cid eq 1.toString()"
test整体用双引号，里面的判断条件单引号并且判断条件加了toString()；
...
choose
!-- test整体使用双引号,判断条件使用单引号 --
when test="cid != null and cid == 1.toString()"
and cid = 1
/when
when test="cid != null and cid == 2.toString()"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
6.1.3 测试
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.1.4 单引号和双引号总结
总结：
test整体用单引号，里面的判断条件双引号；
如果要使用test整体用双引号，里面的判断条件单引号，一定要加toString()；
6.2 == 和 eq 的区别
6.2.1 ==
...
choose
when test=cid != null and cid == "1"
and cid = 1
/when
when test=cid != null and cid == "2"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
6.2.1 测试
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.2.2 eq
...
choose
when test=cid != null and cid eq "1"
and cid = 1
/when
when test=cid != null and cid eq "2"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
6.2.2 测试
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.3 "str" 和 "str".toString() 的区别
6.3.1 "2" 和 "2"toString()
...
choose
when test=cid != null and cid eq "1"
and cid = 1
/when
when test=cid != null and cid eq "2"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
"2".toString()
...
choose
when test=cid != null and cid eq "1".toString()
and cid = 1
/when
when test=cid != null and cid eq "2".toString()
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.3.2 "B" 和 "B".toString() 的区别
...
choose
when test=cid != null and cid eq "A"
and cid = 1
/when
when test=cid != null and cid eq "B"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("B");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
"B".toString()
...
choose
when test=cid != null and cid eq "A".toString()
and cid = 1
/when
when test=cid != null and cid eq "B".toString()
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("B");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.3.3 "22" 和 "22".toString()
choose
when test=cid != null and cid eq "11"
and cid = 1
/when
when test=cid != null and cid eq "22"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("22");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
"22".toString()
...
choose
when test=cid != null and cid eq "11"toString()
and cid = 1
/when
when test=cid != null and cid eq "22"toString()
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("22");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.3.4 "BB" 和 "BB".toString()
...
choose
when test=cid != null and cid eq "AA"
and cid = 1
/when
when test=cid != null and cid eq "BB"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("BB");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
"BB".toString()
...
choose
when test=cid != null and cid eq "AA".toString()
and cid = 1
/when
when test=cid != null and cid eq "BB".toString()
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("BB");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.3.5 "任意字符2" 和 "任意字符2".toString()
"任意字符2"
...
choose
when test=cid != null and cid eq "任意字符1"
and cid = 1
/when
when test=cid != null and cid eq "任意字符2"
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("任意字符2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
"任意字符2".toString()
...
choose
when test=cid != null and cid eq "任意字符1".toString()
and cid = 1
/when
when test=cid != null and cid eq "任意字符2".toString()
and cid = 2
/when
otherwise
and cid = 3
/otherwise
/choose
List Anime animeList = animeMapper.selectAnimesByConditionUserChooseWhenOtherwise("任意字符2");
执行SQL:
-- SQL正常
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE cid = 2
-- 可以查到正确数据
Anime(id=201, cid=2, name=海贼王, author=尾田, actor=路飞, produce=腾讯动漫, createDate=Tue Apr 05 00:00:00 CST 2022)
Anime(id=627, cid=2, name=魁拔3, author=青春树, actor=蛮吉, produce=青春树, createDate=Tue Jan 07 00:00:00 CST 2003)
6.4 总结
只需要将test整体用单引号，里面的判断条件双引号，就可以，加不加.toString(),并不影响；
7、foreach
根据id集合查询动漫集合；
7.1 SQL
7.1.1 起别名 where + foreach (in)
使用 in;
!--List Anime selectAnimesByConditionUserForeach(@Param("ids") List Integer ids);--
select id="selectAnimesByConditionUserForeach" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
where
foreach collection="ids" item="id" open="id in(" close=" )" separator=", "
#{id}
/foreach
/where
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE id in( ? , ? , ? )
7.1.2 不起别名 where + foreach (in)
使用 in;
!-- List Anime selectAnimesByConditionUserForeach( List Integer ids); --
select id="selectAnimesByConditionUserForeach" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
where
foreach collection="list" item="id" open="id in(" close=" )" separator=", "
#{id}
/foreach
/where
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` WHERE id in( ? , ? , ? )
7.1.3 起别名 foreach (in)
不用where标签;
使用 in;
!--List Anime selectAnimesByConditionUserForeach(@Param("ids") List Integer ids);--
select id="selectAnimesByConditionUserForeach" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
foreach collection="ids" item="id" open=" where id in(" close=" )" separator=", "
#{id}
/foreach
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` where id in( ? , ? , ? )
7.1.4 起别名 trim + foreach （in）
不用where标签;
使用 in;
通过7.1.3和7.1.4 可以总结，trim 和 foreach 都有前缀，后缀和分隔符，可以根据情况进项选择使用；
!--List Anime selectAnimesByConditionUserForeach(@Param("ids") List Integer ids);--
select id="selectAnimesByConditionUserForeach" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
trim prefix=" where id in "
foreach collection="ids" item="id" open=" (" close=" )" separator=", "
#{id}
/foreach
/trim
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` where id in ( ? , ? , ? )
7.1.5 起别名 foreach （or）
不用where标签;
使用 or;
!--List Anime selectAnimesByConditionUserForeach(@Param("ids") List Integer ids);--
select id="selectAnimesByConditionUserForeach" resultType="com.kgc.mybatis.bean.Anime"
select `id`,
`cid`,
`name`,
`author`,
`actor`,
`produce`,
`create_date`
from `animes`
foreach collection="ids" item="id" open=" where " close=" " separator=" or "
id = #{id}
/foreach
/select
执行SQL:
Preparing: select `id`, `cid`, `name`, `author`, `actor`, `produce`, `create_date` from `animes` where id = ? or id = ? or id = ?
7.2 测试
@Test
public void testMybatisMapperDynamicSQlUserForeach() throws IOException {
SqlSession defaultSqlSession = getSqlSessionFactory().openSession(true);
//获取mapper接口的代理实现类对象
AnimeMapper animeMapper = defaultSqlSession.getMapper(AnimeMapper.class);
//执行动态SQ。
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