三个表的创建语句

CREATE TABLE `test`.`afx_output_source_item` (`cheadguid` INT NOT NULL,`goodsid` INT NULL,`goodsno` VARCHAR(45) NULL,`goodsname` VARCHAR(45) NULL,`model` VARCHAR(45) NULL,`goodstaxno` VARCHAR(45) NULL,PRIMARY KEY (`cheadguid`));CREATE TABLE `test`.`afx_output_goods` (`goodsno` VARCHAR(45) NULL,`goodstaxno` VARCHAR(45) NULL,`cguid` INT NULL);CREATE TABLE `test`.`afx_output_source_head` (`cguid` INT NOT NULL,`orderno` VARCHAR(45) NULL,`orgncode` VARCHAR(45) NULL,`itype` INT NULL,`status` INT NULL,`createdate` DATETIME NULL,`createuserid` INT NULL,`updateuserid` INT NULL,`orderdate` DATETIME NULL,`voidStatus` INT NULL,`errorStatus` INT NULL,PRIMARY KEY (`cguid`));

原始的关联查询

select * from afx_output_source_item a ,afx_output_goods b, afx_output_source_head c where b.goodsno=a.goodsno and a.model is null and a.cheadguid=c.cguid and c.orderdate>='2024-04-25'

优化后的：

select * from afx_output_goods b inner join   (select * from afx_output_source_item where model is null) a  on b.goodsno=a.goodsno inner join
(select * from afx_output_source_head where orderdate>='2024-04-25')c on a.cheadguid=c.cguid

先过滤表中数据，然后再关联。