¶¯Ì¬sqlÓï¾ä»ù±¾Óï·¨
¶¯Ì¬sqlÓï¾ä»ù±¾Óï·¨
1 :ÆÕͨSQLÓï¾ä¿ÉÒÔÓÃExecÖ´ÐÐ
eg: Select * from tableName
Exec('select * from tableName')
Exec sp_executesql N'select * from tableName' -- Çë×¢Òâ×Ö·û´®Ç°Ò»¶¨Òª¼ÓN
2:×Ö¶ÎÃû£¬±íÃû£¬Êý¾Ý¿âÃûÖ®Àà×÷Ϊ±äÁ¿Ê±£¬±ØÐëÓö¯Ì¬SQL
eg:
declare @fname varchar(20)
set @fname = 'FiledName'
Select @fname from tableName -- ´íÎó,²»»áÌáʾ´íÎ󣬵«½á¹ûΪ¹Ì¶¨ÖµFiledName,²¢·ÇËùÒª¡£
Exec('select ' + @fname + ' from tableName') -- Çë×¢Òâ ¼ÓºÅǰºóµÄ µ¥ÒýºÅµÄ±ßÉϼӿոñ
µ±È»½«×Ö·û´®¸Ä³É±äÁ¿µÄÐÎʽҲ¿É
declare @fname varchar(20)
set @fname = 'FiledName' --ÉèÖÃ×Ö¶ÎÃû
declare @s varchar(1000)
set @s = 'select ' + @fname + ' from tableName'
Exec(@s) -- ³É¹¦
exec sp_executesql @s -- ´
Ïà¹ØÎĵµ£º
A¡£
SQLÓï¾äµÄ²¢¼¯UNION£¬½»¼¯JOIN(ÄÚÁ¬½Ó£¬ÍâÁ¬½Ó)£¬½»²æÁ¬½Ó(CROSS
JOINµÑ¿¨¶û»ý)£¬²î¼¯(NOT IN)
1.
a. ²¢¼¯UNION
SELECT column1, column2 from table1
UNION
SELECT column1, column2 from table2
b. ½»¼¯JOIN
SELECT * from table1 AS a JOIN table2 b ON a.name=b.name
c. ²î¼¯NOT IN
SELECT * from tabl ......
string s = " 80,81,83,82";
string[] s1 = s.Split(',');
int[] p = new int[s1.Count()];
for (int i = 0; i < s1.Count( ......
ÔÎijö´¦£ºhttp://www.dingos.cn/index.php?topic=1874.0
¶¨ÒåºÍÓ÷¨
CONVERT() º¯ÊýÊǰÑÈÕÆÚת»»ÎªÐÂÊý¾ÝÀàÐ͵ÄͨÓú¯Êý¡£
CONVERT() º¯Êý¿ÉÒÔÓò»Í¬µÄ¸ñʽÏÔʾÈÕÆÚ/ʱ¼äÊý¾Ý
Óï·¨
CONVERT(data_type(length),data_to_be_converted,style)
data_type(length) ¹æ¶¨Ä¿±êÊý¾ÝÀàÐÍ£¨´øÓпÉÑ¡µÄ³¤¶È£©¡£data_to_be_conv ......
Orcale µÄSQL Óï¾äÈ¡µÃϵͳµ±Ç°Ê±¼äÓãºsysdate
µ±ÐèÒªÔÚϵͳµ±Ç°ÈÕÆÚÉϼõÈ¥Ò»Ììʱ¿ÉÒÔÓà sysdate-1
¸½£ºµ±Ö»¶ÔÒ»¶¨ÊýÁ¿µÄ¼Ç¼¸ÐÐËȤʱ¿ÉÒÔÈç rownum<100
select * from SLYC_CUSTINFO_T where indbtime>sysdate-1 and OFFICE_CODE='46' and rownum<1 ......
SELECT ID,TITLE,
(SELECT TIMES from CLS_COURSE WHERE CLS_COURSE.ID=CLS_CLASS.COURSEID) AS TIMES,
(SELECT CASE WHEN EXISTS(SELECT * from CLS_ATDC WHERE CLS_ATDC.CLSID=CLS_CLASS.ID ) THEN (SELECT TOP 1 COURSETIME from CLS_ATDC WHERE CLS_ATDC.CLSID=CLS_CLASS.ID ORDER BY COURSETIME DESC) ELSE 0 ......