1.oracle的
substr函式的用法：
取得字串中指定起始位置和長度的字串 substr( string, start_position, [ length ] )。
例：substr('this is a test',6,2) would
return 'is'
substr('this is a test',6) would
return 'is a test'
substr('techonthenet',
-3,3) would
return 'net'
2.將oracle中同一列的多行記錄拼接成乙個字串
用 wm_concat函式:
selectwm_concat(space_full_name) from zd_tobacco_storage_space where tobacco_id =' ' group by tobacco_id
需要排序時：
select ssd.tobacco_id,max(r) from
(select ssd0.space_code,ssd0.tobacco_id, wm_concat(ssd0.space_name)
over (partition by ssd0.tobacco_id order by to_number(ssd0.space_code)) r
from zd_tobacco_storage_space_detai ssd0)ssd
group by ssd.tobacco_id
3.查詢不包含漢字的（ like '%\%' 是包含 ，not like 不包含）
where asciistr(t.tobacco_code) not like '%\%'
4.查詢每條資料當天最後一條
select wh.unit_id,
wh.client_id,
wh.client_name,
wh.large_address_id,
wh.large_address_name,
wh.tobacco_type,
wh.tobacco_state,
wh.tobacco_number,wh.tobacco_weight,wh.change_time,
row_number() over(partition by
wh.tobacco_id
order by
wh.change_time
desc)rn
根據wh.tobacco_idgroup by再根據wh.change_time時間倒序查，該分組rn從1開始
from view_tobaccoreceive_record wh
5.四捨五入
round(to_number(sum(b.afwei))/to_number(decode(sum(b.bfwei),0,1,sum(b.bfwei))),5)
6.類似於三目運算
decode(sum(b.bfwei),0,1,sum(b.bfwei))
當sum(b.bfwei)=0時，取值為1，當sum(b.bfwei)！=0時，取值sum(b.bfwei)
Oracle常用函式
一 row number over 資料甲 1 select column name column name,data type,2 row number over partition by column name order by column name row num 3 from test c...
Oracle常用函式
數學函式 1.絕對值 o select abs 1 value from dual 2.取整 大 o select ceil 1.001 value from dual 3.取整 小 o select floor 1.001 value from dual 4.取整 擷取 o select trun...
oracle常用函式
1.concat c1,c2均為字串，函式將c2連線到c1的後面，如果c1為null,將返回c2.如果c2為null,則返回c1，如果c1 c2都為null，則返回null。他和操作符 返回的結果相同 select concat slobo svoboda username from dualuse...