mybatis plus中如何编写sql语句

 <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.xml</include>
                </includes>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
            </resource>
        </resources>
    </build>

mybatis-plus:
  mapper-locations: classpath*:**/xml/*.xml

baseMapper.countRegisterDay(day)

 Integer countRegisterDay(String day);

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.boshrong.ucentor.mapper.UcenterMemberMapper">
    <select id="countRegisterDay" resultType="java.lang.Integer">
        select count(*) from ucenter_member um where DATE (um.gmt_create)=#{day}
    </select>

</mapper>

 Integer countRegisterDay(String day，String time1);

#{0} 获取day的值， #{1} 获取time1的值

Integer countRegisterDay(@Param ("aa")String day，@Param ("bb")String time1);

max(CONVERT(stat_date,UNSIGNED))

DATE_FORMAT(update_time,‘%Y-%m-%d %T')

concat(#{year},‘Y')

DATE_FORMAT(DATE_SUB(CURDATE(),interval -1 year),‘%Y')

DATE_FORMAT(CURDATE(),‘%Y')

right(args, 2)

pay_time <![CDATA[<]]> now() - INTERVAL 3 MONTH AND now()

SUBSTRING_INDEX( dep_name, ‘-',- 1 ) depName

SUBSTRING_INDEX( dep_name, ‘-',1 ) depName

GREATEST(expr1, expr2, expr3, …)

LEAST(expr1, expr2, expr3, …)

DATEDIFF(d1,d2)

IF(expr,v1,v2)

AND (TRIM(str） REGEXP ‘[^0-9.]') = 0

CAST(right(yearmth, 2) AS SIGNED)

FIND_IN_SET (year_id,(SELECT
GROUP_CONCAT(DISTINCT LEFT(字段, 4))
from table))

// 如果字符串 string 包含 subStr
locate(subStr,string) > 0
// 如果字符串 string 不包含 subStr
locate(subStr,string) = 0

select * from user where locate('王',name)

select * from user where locate('王',name,2)