MyBatis（4）-- 动态SQL
如果使用JDBC或者类似于Hibernate的其他框架，很多时候要根据需要去拼装SQL，这是一个麻烦的事情。因为某些查询需要许多条件。通常使用其他框架需要大量的Java代码进行判断，可读性比较差，而MyBatis提供对SQL语句动态的组装能力，使用XML的几个简单的元素，便能完成动态SQL的功能。大量的判断都可以在MyBatis的映射XML里面配置，以达到许多需要大量代码才能实现的功能，大大减少了代码量，这体现了MyBatis的灵活、高度可配置性和可维护性。
MyBatis的动态SQL包括以下几种元素：
数据库MySQL中表：
mysql> select * from t_role;
+----+-------------+--------+
| id | role_name | note |
+----+-------------+--------+
| 1 | role_name_1 | note_1 |
| 2 | role_name_2 | note_2 |
| 3 | role_name_3 | note_3 |
+----+-------------+--------+
3 rows in set (0.00 sec)
1.if元素
if元素是最常见的判断语句，常常与test属性联合使用。
<select id="findRole1" parameterType="string" resultMap="roleResultMap">
select role_no, role_name, note from t_role where 1=1
<if test="roleName != null and roleName !=''">
and role_name like concat('%', #{roleName}, '%')
</if>
</select>
解决如下需求：需要根据角色名称（roleName）去查找角色，但是角色名称是一个选填条件，如果不填写，就不要用它作为条件查询。
当参数roleName传递进映射器时，如果参数不为空，则采取构造对roleName的模糊查询，否则就不要去构造这个条件。
接口：
public List<Role> findRole1(@Param("roleName") String roleName);
测试方法：
public static void testFindRole1() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
List<Role> roleList = roleMapper.findRole1("role_name");
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
日志输出结果：
DEBUG 2018-10-08 21:07:32,127 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,375 org.apache.ibatis.datasource.pooled.PooledDataSource: Created connection 1384722895.
DEBUG 2018-10-08 21:07:32,375 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,377 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: select id, role_name, note from t_role where 1=1 and role_name like concat('%', ?, '%')
DEBUG 2018-10-08 21:07:32,400 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: role_name(String)
DEBUG 2018-10-08 21:07:32,424 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 3
3
DEBUG 2018-10-08 21:07:32,425 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,425 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,426 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
2.choose、when、otherwise元素
<select id="findRole2" parameterType="role" resultMap="roleResultMap">
select role_no, role_name, note from t_role
where 1=1
<choose>
<when test="roleNo != null and roleNo !=''">
AND role_no = #{roleNo}
</when>
<when test="roleName != null and roleName !=''">
AND role_name like concat('%', #{roleName}, '%')
</when>
<otherwise>
AND note is not null
</otherwise>
</choose>
</select>
需求：
- 如果角色编号（roleNo）不为空，则只用角色编号作为条件查询
- 当角色编号为空，而角色名称不为空时，则用角色名称作为条件进行模糊查询
- 当角色编号和角色名称都为空时，则要求角色备注不为空。
接口：
public List<Role> findRole2(Role role);
测试方法：
public static void testFindRole2() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
Role role = new Role();
role.setRoleNo("role_no_1");
role.setRoleName("role_name");
List<Role> roleList = roleMapper.findRole2(role);
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,426 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,427 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,429 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,431 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: select id, role_name, note from t_role where 1=1 AND id = ?
DEBUG 2018-10-08 21:07:32,431 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: role_no_1(String)
DEBUG 2018-10-08 21:07:32,432 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 0
0
DEBUG 2018-10-08 21:07:32,432 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,432 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,432 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
3.trim、where、set元素
（1）使用where元素
<select id="findRole3" parameterType="role" resultMap="roleResultMap">
select role_no, role_name, note from t_role
<where>
<if test="roleName != null and roleName !=''">
and role_name like concat('%', #{roleName}, '%')
</if>
<if test="note != null and note !=''">
and note like concat('%', #{note}, '%')
</if>
</where>
</select>
对比于上面的choose、when和otherwise元素，使用where元素可以去掉条件“1=1”。当where元素里面的条件成立时，才会加入where这个SQL关键字到组装的SQL里面，否则就不加入。
接口：
public List<Role> findRole3(Role role);
测试方法：
public static void testFindRole3() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
Role role = new Role();
role.setRoleNo("role_no_1");
role.setRoleName("role_name");
List<Role> roleList = roleMapper.findRole3(role);
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,433 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,433 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,433 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,434 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: select id, role_name, note from t_role WHERE role_name like concat('%', ?, '%')
DEBUG 2018-10-08 21:07:32,434 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: role_name(String)
DEBUG 2018-10-08 21:07:32,436 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 3
3
DEBUG 2018-10-08 21:07:32,436 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,436 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,437 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
（2）使用trim元素
<select id="findRole4" parameterType="string" resultMap="roleResultMap">
select role_no, role_name, note from t_role
<trim prefix="where" prefixOverrides="and">
<if test="roleName != null and roleName !=''">
and role_name like concat('%', #{roleName}, '%')
</if>
</trim>
</select>
trim元素意味着要去掉一些特殊的字符串，prefix代表的是语句的前缀，而prefixOverrides代表的是需要去掉哪种字符串，上面的写法基本与where是等效的。
即如果and成立，就使用where条件；否则，不使用where条件与and条件。
接口：
public List<Role> findRole4(@Param("roleName") String roleName);
测试方法：
public static void testFindRole4() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
List<Role> roleList = roleMapper.findRole4("role_name");
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,437 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,437 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,439 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,439 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: select id, role_name, note from t_role where role_name like concat('%', ?, '%')
DEBUG 2018-10-08 21:07:32,439 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: role_name(String)
DEBUG 2018-10-08 21:07:32,440 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 3
3
DEBUG 2018-10-08 21:07:32,440 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,441 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,441 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
（3）使用set元素
<update id="updateRole" parameterType="role">
update t_role
<set>
<if test="roleName != null and roleName !=''">
role_name = #{roleName},
</if>
<if test="note != null and note != ''">
note = #{note}
</if>
</set>
where id = #{roleNo}
</update>
set元素遇到了逗号，它会把对应的逗号去掉。这样当只想更新备注时，只需要传递备注信息和角色编号即可，而不需要再传递角色名称。MyBatis就会根据参数的规则进行动态SQL组装，这样便能满足要求，而避免全部字段更新的问题。
接口：
public int updateRole(Role role);
测试方法：
public static void testUpdateRole() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
Role role = new Role();
role.setNote("note_1_update");
role.setRoleName("role_name_1_update");
role.setRoleNo("role_no_1");
int result = roleMapper.updateRole(role);
System.out.println(result);
sqlSession.commit();
} catch(Exception ex) {
sqlSession.rollback();
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,449 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,449 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,450 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,450 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: update t_role SET role_name = ?, note = ? where id = ?
DEBUG 2018-10-08 21:07:32,450 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: role_name_1_update(String), note_1_update(String), role_no_1(String)
DEBUG 2018-10-08 21:07:32,451 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Updates: 0
0
DEBUG 2018-10-08 21:07:32,452 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Committing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,452 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,452 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,452 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
4.foreach元素
<select id="findRoleByNums" resultMap="roleResultMap">
select id, role_name, note from t_role where id in
<foreach item="roleNo" index="index" collection="roleNoList"
open="(" separator="," close=")">
#{roleNo}
</foreach>
</select>
foreach元素是一个循环语句，它的作用是遍历集合，能够很好地支持数组和List、Set接口的集合，对此提供遍历功能。往往用于SQL中的in关键字。
- collection配置的roleNoList是传递进来的参数名称，它可以是一个数组、List、Set等集合
- item配置的是当前元素在集合的位置下标
- index配置的是当前元素在集合的位置下标
- open和close配置的是以什么符号将这些集合元素包装起来
- separator是各个元素的间隔符
接口：
public List<Role> findRoleByNums(@Param("roleNoList") List<String> roleNoList);
测试方法：
public static void testFindRoleByNums() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
List<String> roleNoList = new ArrayList<String>();
roleNoList.add("role_no_1");
roleNoList.add("role_no_2");
roleNoList.add("role_no_3");
List<Role> roleList = roleMapper.findRoleByNums(roleNoList);
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,454 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,454 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,455 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,455 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: select id, role_name, note from t_role where id in ( ? , ? , ? )
DEBUG 2018-10-08 21:07:32,456 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: role_no_1(String), role_no_2(String), role_no_3(String)
DEBUG 2018-10-08 21:07:32,456 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 0
0
DEBUG 2018-10-08 21:07:32,457 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,457 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,457 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
5.用test的属性判断字符串
<select id="getRoleTest" parameterType="string" resultMap="roleResultMap">
select id, role_name, note from t_role
<if test="type == 'Y'.toString()">
where 1=1
</if>
</select>
如果把type=“Y”传递给SQL，就可以发现MyBatis加入了条件where 1=1。
对于字符串的判断，可以通过加入toString()方法进行比较。
接口：
public List<Role> getRoleTest(@Param("type") String type);
测试方法：
public static void testGetRoleTest() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
List<Role> roleList = roleMapper.getRoleTest("Y");
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,461 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,461 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,461 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,462 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: select id, role_name, note from t_role where 1=1
DEBUG 2018-10-08 21:07:32,462 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters:
DEBUG 2018-10-08 21:07:32,464 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 3
3
DEBUG 2018-10-08 21:07:32,464 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,464 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,464 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
6.bind元素
bind元素的作用是通过OGNL表达式去自定义一个上下文变量，这样更方便使用。
（1）使用bind元素绑定单个参数
<select id="findRole5" parameterType="string" resultMap="roleResultMap">
<bind name="pattern" value="'%' + _parameter + '%'" />
SELECT id, role_name, note FROM t_role
where role_name like #{pattern}
</select>
“_parameter”表示传递进来的参数，它和通配符（%）连接后赋给了pattren变量，然后就可以在select语句中使用这个变量进行模糊查询了。
接口：
public List<Role> findRole5(String roleName);
测试方法：
public static void testFindRole5() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
List<Role> roleList = roleMapper.findRole5("role_name");
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,443 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,444 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,444 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,444 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: SELECT id, role_name, note FROM t_role where role_name like ?
DEBUG 2018-10-08 21:07:32,444 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: %role_name%(String)
DEBUG 2018-10-08 21:07:32,446 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 3
3
DEBUG 2018-10-08 21:07:32,446 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,446 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,446 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
（2）使用bind元素绑定多个参数
<select id="findRole6" resultMap="roleResultMap">
<bind name="pattern_roleName" value="'%' + roleName + '%'" />
<bind name="pattern_note" value="'%' + note + '%'" />
SELECT id, role_name, note FROM t_role
where role_name like
#{pattern_roleName}
and note like #{pattern_note}
</select>
这里绑定了两个新的变量pattern_roleName和pattern_note，然后就可以在SQL的其他地方使用了，如进行模糊查询。
接口：
public List<Role> findRole6(@Param("roleName") String roleName, @Param("note") String note);
测试方法：
public static void testFindRole6() {
SqlSession sqlSession = null;
try {
sqlSession = SqlSessionFactoryUtils.openSqlSession();
RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
List<Role> roleList = roleMapper.findRole6("role_name", "note");
System.out.println(roleList.size());
} catch(Exception ex) {
ex.printStackTrace();
} finally {
if (sqlSession != null) {
sqlSession.close();
}
}
}
结果：
DEBUG 2018-10-08 21:07:32,447 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Opening JDBC Connection
DEBUG 2018-10-08 21:07:32,447 org.apache.ibatis.datasource.pooled.PooledDataSource: Checked out connection 1384722895 from pool.
DEBUG 2018-10-08 21:07:32,447 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,447 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Preparing: SELECT id, role_name, note FROM t_role where role_name like ? and note like ?
DEBUG 2018-10-08 21:07:32,448 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: ==> Parameters: %role_name%(String), %note%(String)
DEBUG 2018-10-08 21:07:32,448 org.apache.ibatis.logging.jdbc.BaseJdbcLogger: <== Total: 3
3
DEBUG 2018-10-08 21:07:32,449 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Resetting autocommit to true on JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,449 org.apache.ibatis.transaction.jdbc.JdbcTransaction: Closing JDBC Connection [com.mysql.jdbc.JDBC4Connection@528931cf]
DEBUG 2018-10-08 21:07:32,449 org.apache.ibatis.datasource.pooled.PooledDataSource: Returned connection 1384722895 to pool.
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