select
<include refid="AlarmStatistics_List" />
from (
selectvehicle.vehicleid,vehicle.Platenumber,
COUNT(devicerunning.deviceid)Total,
sum(decode(Warningtypeid,1,1,2,1,3,1,0))TypeA,
sum(decode(Warningtypeid,4,1,5,1,6,1,7,1,8,1,9,1,10,1,0))TypeB,
sum(decode(Warningtypeid,11,1,12,1,13,1,0))TypeC,
sum(decode(Warningtypeid,1,1,0))as Type1,
sum(decode(Warningtypeid,2,1,0))as Type2,
sum(decode(Warningtypeid,3,1,0))as Type3,
sum(decode(Warningtypeid,4,1,0))as Type4,
sum(decode(Warningtypeid,5,1,0))as Type5,
sum(decode(Warningtypeid,6,1,0))as Type6,
sum(decode(Warningtypeid,7,1,0))as Type7,
sum(decode(Warningtypeid,8,1,0))as Type8,
sum(decode(Warningtypeid,9,1,0))as Type9,
sum(decode(Warningtypeid,10,1,0))as Type10,
sum(decode(Warningtypeid,11,1,0))as Type11,
sum(decode(Warningtypeid,12,1,0))as Type12,
sum(decode(Warningtypeid,13,1,0))as Type13
以上代碼sum函式中的decode函式在mysql沒有，所以試著改成sum(case when Warningtypeid=1 then 1······when Warningtypeid=3 then 1 else 0 end)TypeA, 報格式錯誤，請問應該怎么改
uj5u.com熱心網友回復：
參考 樓主 qq_41606102 的回復: select
case when end結構mysql中應該也可以，但你也可以if試試。
select case when c1=1 then 'aa' when c1=2 then 'bb' when c1=3 then 'cc' else 'dd' end from t1;
select if(c1=1,'aa',if(c1=2,'bb',if(c1=3,'cc','dd'))) from t1;
uj5u.com熱心網友回復：
參考 1 樓 lhdz_bj 的回復: Quote: 參考 樓主 qq_41606102 的回復: 謝謝！嘗試了你的if陳述句可以了，之前也寫過if陳述句，和你的對比之后發現出錯原因在于嵌套沒打上括號（我之前寫的是if eslif else，發現也報格式錯誤~）
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標籤：MySQL
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