数据库中多表关联查询。
select c.CARCARDNUMBER as 车牌号码,'蓝牌' as 车牌颜色,'小型轿车' as 车辆类型,'出租客运' as 使用性质,c.CARBRAND as 车辆品牌,c.CARVERSION as 车辆型号,c.ISDOUBLEFULE as 是否双燃料车,
fu.name as 燃料种类,c.REGISTERDATE as 注册日期,a.checktime as 最后一次检查时间,d.stationname as 检测站,m.name as 检测方法
from BAS_CARINFO c
inner join (select mas.* from INS_CHECKRESULTMAIN mas inner join (select carpkid,max(checktime) as checktime from INS_CHECKRESULTMAIN group by carpkid) ma on mas.carpkid=ma.carpkid and mas.checktime=ma.checktime) a on a.carpkid=c.pkid
INNER JOIN BAS_CHECKSTATION d on d.PKID=a.stationpkid
left join COD_CARDCOLOR e on e.code=c.carcardcolor
left join COD_CARMODE f on f.code=c.CARMODE
left join COD_CHECKMETHOD m on m.code=a.checkmethod
left join cod_FUELTYPE fu on fu.code=c.fueltype
where "TO_CHAR"(a.checktime,'yyyy-mm-dd')>='2019-05-01' and "TO_CHAR"(a.checktime,'yyyy-mm-dd')<='2019-11-01' and c.USEDQUALITY='33' and c.CARMODECODE='K33'
order by STATIONNAME,checktime
select t.name 姓名,t.password from table t ; t表示替换字符,可以用t直接点出。姓名表示 索引头用姓名替代name. as这个可有可无
inner join left join 添加关联
to_date('2020-02-02','yyyy-mm-dd') 查询的时间表示方法
on 用来关联表中的字段对应另一张表中的字段