mysql存储过程如何利用临时表返回结果集
目录
- 首先要声明的是
- 测试示例
- 真实需求,查找出所有用建单情况
首先要声明的是
1,游标的方法会很慢在mysql中,在oracle数据库中还可以,除非没有别的方法,一般不建议在mysql中使用游标,
2,不建议在mysql中拼接sql,会使存储过程显得很臃肿,可以使用or来动态判别传入的参数是否为空
and ( TTB.office_id=输入参数 or 输入参数 is null or 输入参数 = '') and ( TTB.office_id=IN_Office_id or IN_Office_id is null or IN_Office_id = '')
3,不建议使用临时表来存储多用户下经常查询的内容,比如报表
4,返回结果集更好的方法是直接链接多个表返回结果集即可,下面的示例虽然给以得到正确结果,
但代码臃肿,速度异常的慢,可以当个反面教材
5,优化后的存储过程:https://www.jb51.net/article/263729.htm
测试示例
BEGIN #创建一个临时表 DROP TABLE if exists user_temporary; create temporary table if not exists user_temporary ( id VARCHAR(64) primary key,#id user_name VARCHAR(20) #姓名 ) ; begin #定义 变量 接收id和姓名 declare a VARCHAR(64); declare b VARCHAR(20); #这个用于处理游标到达最后一行的情况 DECLARE s int default 0; #声明游标cursor_name(cursor_name是个多行结果集) DECLARE cursor_name CURSOR FOR select id ,name from user ; #设置一个终止标记 DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET s=1; #打开游标 OPEN cursor_name; #获取游标当前指针的记录,读取一行数据并传给变量a,b fetch cursor_name into a,b; #开始循环,判断是否游标已经到达了最后作为循环条件 while s <> 1 do insert into user_temporary(id,user_name) values(a,b); #读取下一行的数据 fetch cursor_name into a,b; end while; #关闭游标 CLOSE cursor_name ; #从临时表中拿到结果集 SELECT * from user_temporary; #语句执行结束 end; END
注意类型 为存储过程 procedure 不是存储函数function
运行结果:
真实需求,查找出所有用建单情况
BEGIN DROP TABLE if exists user_temporary; create temporary table if not exists user_temporary ( id VARCHAR(64) primary key,id user_name VARCHAR(20) ,#姓名 company_name VARCHAR(20) ,#所属公司 worksheet_num INTEGER, #机会点总数 sign_worksheet_num INTEGER ,#签单数量 exchange_num INTEGER ,#填写交流记录次数 sales_volume double(20,2) #销售额 ) ; begin #定义 变量 declare a_id VARCHAR(64); declare b_user_name VARCHAR(20); declare c_company_name VARCHAR(20); declare d_worksheet_num int ; declare e_sign_worksheet_num int ; declare f_exchange_num int ; declare g_sales_volume double(20,2) ; #这个用于处理游标到达最后一行的情况 DECLARE s int default 0; #声明游标cursor_name(cursor_name是个多行结果集) DECLARE cursor_name CURSOR FOR select a.id ,a.name ,o.name AS company_name from sys_user a LEFT JOIN sys_office o on a.company_id =o.id; #设置一个终止标记 DECLARE CONTINUE HANDLER FOR SQLSTATE '02000' SET s=1; #打开游标 OPEN cursor_name; #获取游标当前指针的记录,读取一行数据并传给变量a,b fetch cursor_name into a_id,b_user_name ,c_company_name; #开始循环,判断是否游标已经到达了最后作为循环条件 while s <> 1 do #读取下一行的数据 #声明输入变量,以便在sql串中拼接 set @userId=a_id; set @beginDate=begin_date; set @endDate=end_date; #收集总机会点 有if判断用拼接sql,然后再解析执行sql, set @exesqlAll =CONCAT('SELECT count(1) into @handle_num FROM crm_worksheet where create_by=@userId and del_flag=0 '); IF begin_date is not null and begin_date !='' THEN set @exesqlAll =CONCAT(@exesqlAll,' AND TO_DAYS(create_date) >=TO_DAYS(@beginDate)'); END IF; IF end_date is not null and end_date !='' THEN set @exesqlAll =CONCAT(@exesqlAll,' AND TO_DAYS(create_date) <=TO_DAYS(@endDate)'); END IF; prepare allWorksheet from @exesqlAll; #解析sql execute allWorksheet; #执行sql DEALLOCATE prepare allWorksheet; #释放sql SET d_worksheet_num = @handle_num; #变量赋值 IF d_worksheet_num > 0 THEN set @exesqlSign =CONCAT('SELECT count(1) into @sign_num FROM crm_worksheet where create_by=@userId and del_flag=0 and important_degree=''sys_basic_qian_shu_he_tong'' '); IF begin_date is not null and begin_date !='' THEN set @exesqlSign =CONCAT(@exesqlSign,' AND TO_DAYS(create_date) >=TO_DAYS(@beginDate)'); END IF; IF end_date is not null and end_date !='' THEN set @exesqlSign =CONCAT(@exesqlSign,' AND TO_DAYS(create_date) <=TO_DAYS(@endDate)'); END IF; prepare signWorksheet from @exesqlSign; execute signWorksheet; DEALLOCATE prepare signWorksheet; SET e_sign_worksheet_num = @sign_num; #收集交流次数 set @exesqlExchange =CONCAT('SELECT COUNT(1) into @exchange_num from crm_wkst_exchange_record e LEFT JOIN crm_worksheet w on e.worksheet_no= w.worksheet_no where w.create_by=@userId and w.del_flag=0'); IF begin_date is not null and begin_date !='' THEN set @exesqlExchange =CONCAT(@exesqlExchange,' AND TO_DAYS(w.create_date) >=TO_DAYS(@beginDate)'); END IF; IF end_date is not null and end_date !='' THEN set @exesqlExchange =CONCAT(@exesqlExchange,' AND TO_DAYS(w.create_date) <=TO_DAYS(@endDate)'); END IF; prepare exchangeWorksheet from @exesqlExchange; execute exchangeWorksheet; DEALLOCATE prepare exchangeWorksheet; SET f_exchange_num = @exchange_num; #收集销售额 set @exesqlSales =CONCAT('SELECT (@sumSalary := @sumSalary + solution) AS count into @sales_num FROM crm_worksheet cw , (SELECT @sumSalary := 0) b WHERE cw.create_by=@userId and important_degree=''sys_basic_qian_shu_he_tong'' and cw.del_flag=0 ORDER BY count desc limit 1 '); IF begin_date is not null and begin_date !='' THEN set @exesqlExchange =CONCAT(@exesqlExchange,' AND TO_DAYS(cw.create_date) >=TO_DAYS(@beginDate)'); END IF; IF end_date is not null and end_date !='' THEN set @exesqlExchange =CONCAT(@exesqlExchange,' AND TO_DAYS(cw.create_date) <=TO_DAYS(@endDate)'); END IF; prepare salesWorksheet from @exesqlSales; execute salesWorksheet; DEALLOCATE prepare salesWorksheet; SET g_sales_volume = @sales_num; ELSE SET e_sign_worksheet_num=0; SET f_exchange_num=0; SET g_sales_volume=0; END IF; insert into user_temporary(id,user_name,company_name,sign_worksheet_num,exchange_num,worksheet_num,sales_volume) values(a_id,b_user_name,c_company_name,e_sign_worksheet_num,f_exchange_num,d_worksheet_num,g_sales_volume); #插入临时表 fetch cursor_name into a_id,b_user_name ,c_company_name; end while; #关闭游标 CLOSE cursor_name ; #从临时表中查出结果集 set @userIdInput=user_id; set @exesqlResult =CONCAT('SELECT user_name,company_name,sign_worksheet_num,exchange_num,worksheet_num,sales_volume from user_temporary'); IF user_id is not null and user_id !='' THEN set @exesqlResult =CONCAT(@exesqlResult,' where id = @userIdInput'); END IF; prepare resultUser from @exesqlResult; execute resultUser; DEALLOCATE prepare resultUser; #语句执行结束 end; END
运行结果
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