sql取第一條記錄
⑴ 如何取sql結果集的第一條記錄
在SQL Server資料庫中,使用top關鍵字:
SELECT TOP number|percent column_name(s) FROM table_name
在MySQL資料庫中,使用LIMIT關鍵字:
SELECT column_name(s) FROM table_name LIMIT number
例子:SELECT * FROM Persons LIMIT 1
在Oracle資料庫中,使用ROWNUM關鍵字:
SELECT column_name(s) FROM table_name WHERE ROWNUM <= number
例子:SELECT * FROM Persons WHERE ROWNUM <= 1
⑵ sql取出第一條數據
select top 1 col1,col2 from tblname where col3='111' order by col1 desc;
試一下
⑶ 如何用SQL SERVER取分組數據第一條
根據table1_id進行分組所得結果:
select * from (select a.id as a_id,a.name,a.time,a.content,b.id as b_id,b.user from table1 a inner join table2 b on a.id = b.table1_ID) new_tbl where b_id in (select min(id) from table2 group by table1_ID)
(3)sql取第一條記錄擴展閱讀:
注意事項
在SQL Server資料庫中,使用top關鍵字:SELECT TOP number|percent column_name(s) FROM table_name
在MySQL資料庫中,使用LIMIT關鍵字:SELECT column_name(s) FROM table_name LIMIT number
例子:SELECT * FROM Persons LIMIT 1
select bookName from book where price > 20 limit 1;
limit 1;
or
limit 0,1;
在Oracle資料庫中,使用ROWNUM關鍵字:
SELECT column_name(s) FROM table_name WHERE ROWNUM <= number
例子:SELECT * FROM Persons WHERE ROWNUM <= 1
⑷ sql語句,根據關鍵字,取第一條數據
select No,Count,max(Time) as Time
from 表
group by No,Count
⑸ sql語句,選第一條數據
幾個常用資料庫的寫法如下:
1、mssql資料庫
selecttop1*fromtable
2、Oracle資料庫
select*fromtablewhererownum<2
3、MySQL資料庫:
select*fromtablelimit0,1
(這里keyword limit startid,rownum是這樣的:表示從startid + 1行開始,一共查詢rownum條記錄。
⑹ sql根據某一個欄位重復只取第一條數據
代碼如下:
select * from tbl_DPImg where ID in (select min(ID) from tbl_DPImg group by DPID)
處理後結果為:
查找表中多餘的重復記錄,重復記錄是根據單個欄位(teamId)來判斷
select * from team where teamId in (select teamId from team group by teamId having count(teamId) > 1)
刪除表中多餘的重復記錄,重復記錄是根據單個欄位(teamId)來判斷,只留有rowid最小的記錄
delete from team where
teamName in(select teamName from team group by teamName having count(teamName) > 1)
and teamId not in (select min(teamId) from team group by teamName having count(teamName)>1)
(6)sql取第一條記錄擴展閱讀
數據記錄篩選:
sql="select * from 數據表 where欄位名=欄位值 order by欄位名[desc]"(按某個欄位值降序排列。默認升序ASC)
sql="select * from 數據表 where欄位名like '%欄位值%' order by 欄位名 [desc]"
sql="select top 10 * from 數據表 where欄位名=欄位值 order by 欄位名 [desc]"
sql="select top 10 * from 數據表 order by 欄位名 [desc]"
sql="select * from 數據表 where欄位名in ('值1','值2','值3')"
sql="select * from 數據表 where欄位名between 值1 and 值2"
⑺ SQL 怎麼查詢每個人的第一條數據
select
mid ,content
from(
SELECT
mid ,content,
rank() over(ORDER BY content) as rank1
FROM tb_record) a
where a.rank1=1
⑻ sql如何查詢第一個數據
sql如何查詢第一個數據的方法。
如下參考:
1.首先,雙擊「ManagementStudio」圖標打開SQLServer。
⑼ 要取一個欄位中按照排序後的第一條記錄,SQL語句怎麼寫
如果支持first函數就用:
SELECT FIRST(column_name) FROM pers_customer ORDER BY column_name
不支持可以用:
select * from (select * from table_name order by column_name) where rownum = 1
⑽ 如何取sql中的第一條
select top1 col1,col2 from tblname where col3='111' order by col1 desc;