两张表的联立视图查询:
创建视图的sql语句:
SELECT
t_employee_info.employee_name,
t_employee_info.employee_age,
t_employee_info.employee_address,
t_salary_info.salary_id,
t_salary_info.time,
t_salary_info.money,
t_employee_info.employee_id
FROM
t_employee_info
INNER JOIN t_salary_info ON t_salary_info.employee_id = t_employee_info.employee_id
ORDER BY
t_salary_info.money DESC
创建存储过程的sql语句:
BEGIN
#Routine body goes here...
select
t_employee_info.employee_name,
t_employee_info.employee_age,
t_employee_info.employee_address,
t_employee_info.employee_id,
t_salary_info.salary_id,
t_salary_info.time,
t_salary_info.money
FROM t_employee_info INNER JOIN t_salary_info
ON t_salary_info.employee_id = t_employee_info.employee_id
where t_employee_info.employee_id=employee_id
ORDER BY
t_salary_info.money DESC limit 10;
END
mybatis的mapper.xml代码:
<?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.jm.dao.TEmployeeSalaryMapper">
<resultMap id="BaseResultMap" type="com.jm.model.TEmployeeSalary">
<result column="employee_id" property="employeeId" jdbcType="BIGINT" />
<result column="employee_name" property="employeeName" jdbcType="VARCHAR" />
<result column="employee_age" property="employeeAge" jdbcType="INTEGER" />
<result column="employee_address" property="employeeAddress" jdbcType="VARCHAR" />
<result column="salary_id" property="salaryId" jdbcType="BIGINT" />
<result column="time" property="time" jdbcType="BIGINT" />
<result column="money" property="money" jdbcType="BIGINT" />
</resultMap>
<!-- 调用存储过程查询 -->
<select id="loadByEmployeeId" parameterType="Long" statementType="CALLABLE" resultMap="BaseResultMap">
{call employee_salary_function(#{employeeId,jdbcType=BIGINT,mode=IN})}
</select>
<!-- 调用视图查询 -->
<select id="loadByEmployeeIdView" resultMap="BaseResultMap">
select * from v_employee_salary where employee_id=#{employeeId,jdbcType=BIGINT}
</select>
</mapper>
实体类:
public class TEmployeeSalary {
private Long employeeId;
private String employeeName;
private Integer employeeAge;
private String employeeAddress;
private Long salaryId;
private Long time;
private Long money;
public String toString(){
return "employeeId:"+employeeId+", "+"employeeName:"+employeeName+", "+"employeeAge:"+employeeAge+", "+"employeeAddress:"+employeeAddress+", "+
"salaryId:"+salaryId+", "+"time:"+time+", "+"money:"+money+"-----------";
}
public Long getEmployeeId() {
return employeeId;
}
public void setEmployeeId(Long employeeId) {
this.employeeId = employeeId;
}
public String getEmployeeName() {
return employeeName;
}
public void setEmployeeName(String employeeName) {
this.employeeName = employeeName;
}
public Integer getEmployeeAge() {
return employeeAge;
}
public void setEmployeeAge(Integer employeeAge) {
this.employeeAge = employeeAge;
}
public String getEmployeeAddress() {
return employeeAddress;
}
public void setEmployeeAddress(String employeeAddress) {
this.employeeAddress = employeeAddress;
}
public Long getSalaryId() {
return salaryId;
}
public void setSalaryId(Long salaryId) {
this.salaryId = salaryId;
}
public Long getTime() {
return time;
}
public void setTime(Long time) {
this.time = time;
}
public Long getMoney() {
return money;
}
public void setMoney(Long money) {
this.money = money;
}
}
dao:
import java.util.List;
import org.apache.ibatis.annotations.Param;
import com.jm.model.TEmployeeSalary;
public interface TEmployeeSalaryMapper {
/**
* loadByEmployeeId:根据雇员的id获取他的工资情况,存储过程的调用
* @author JM
* 2016-12-14 下午11:17:54
* @param id
* @return
* List<TEmployeeSalary>
*/
public List<TEmployeeSalary> loadByEmployeeId(@Param("employeeId")Long id);
/**
* loadByEmployeeIdView:根据雇员的id获取他的工资情况,视图的调用
* @author JM
* 2016-12-14 下午11:40:36
* @param id
* @return
* List<TEmployeeSalary>
*/
public List<TEmployeeSalary> loadByEmployeeIdView(@Param("employeeId")Long id);
}
以上就是使用mybatis,调用视图查询以及存储过程的实现代码。
许多情况下,对数据库进行多表查询可以使用视图进行联系多表,但是不建议使用视图进行查询(因为不可以输入参数,每次查询都需要全部查出来然后在挑选出符合条件的数据,这样大大拖慢了查询的速度),调用存储过程进行多表查询的好处就是先进性筛选然后在返回数据,这样的查询速度在数据量很大的情况下快的不是一星半点。
虽然存储过程的使用可以大大提高查询速率,但是对于频繁操作的表本人强烈建议添加索引,这样效率更高。