问下各位大佬，我现在写了一个sql的环比同比这2个字段但是得不到值，我是哪块没写对SELECT city_code 城市,sum(case when left(week_start,7)='${month}' then average_transaction_priceend) 当月商品住宅成交均价,sum(case when left(week_start,7)='${month}' then depolarization_cycle end) 当月库存去化周期,sum(case when left(week_start,4)=left('${month}',4) then average_transaction_price * number_of_transactionsend) 当年月商品住宅成交额,sum(case when left(week_start,7)='${month}'then average_transaction_price * number_of_transactionsend) 当月商品住宅成交额,sum(case when left(week_start,4)= CONVERT(varchar(4),DATEADD(year,-1,'${month}'+'-01'), 20)then average_transaction_price * number_of_transactions end) 去年商品住宅成交额,sum(case when left(week_start,7)= CONVERT(varchar(7),DATEADD(month,-1,'2021-01'+'-01'), 20)then average_transaction_price * number_of_transactions end) 上月商品住宅成交额FROM .where 1=1 ${if(city_code=='x00000',""," and city_code = '"+city_code+"'")} and enable = 1and (left(week_start,7) = '2021-07 ') or (left(week_start,7) =CONVERT(varchar(7),DATEADD(month,-1,'2021-07'+'-01'), 20) )and(left(week_start,4) = '2021 ') or (left(week_start,4) = CONVERT(varchar(4),DATEADD(year,-1,'2021-07'+'-01'), 20) )group by city_code
