Æ´½ÓSQLÔì³ÉµÄÒâÏë²»µ½µÄºó¹û
Ö´ÐÐÊý¾Ý²Ù×÷ʱ£¬ÓÉÓÚÆ´½ÓSQL´æÔÚÖÖÖÖ±×¶Ë£¬Ôç¾ÍÓ¦¸ÃÅׯúÁË£¬µ«ÔÚÏÖʵ¿ª·¢Ê±£¬ÓÖÓÉÓÚÖÖÖÖÔÒò£¬¹«Ë¾Ò»Ö±²ÉÓÃÕâÖÖ·½Ê½£¨UI²ãºÍÂß¼²ã¶¼ÓÐÑϸñµÄ¹ýÂË£¬µ¹Ò²Ã»³öÏÖ¹ýʲôÎÊÌ⣩£¬µ«×òÌ쿪·¢Ê±È´³öÏÖÁËÒâÏë²»µ½µÄÎÊÌ⣬һ¸ö¼òµ¥µÄÓï¾ä»áÔì³ÉÑÏÖØºó¹û¡£¼òµ¥µÄÓï¾äʾÀýÈçÏ£º
/// <summary>
/// ¸üÐÂÖ÷¼üΪ2µÄ¼Ç¼µÄ×ÜÇ®Êý
/// </summary>
/// <param name="totalMoney">Ð޸ĺóµÄ×ÜÇ®Êý</param>
public void UpdateTotalMoney(int totalMoney)
{
int id = 2; //Êý¾Ý¿â±íÖ÷¼ü
int oldTotalMoney = 5000; //Ö÷¼üΪ2µÄ¼Ç¼ÔÀ´µÄ×ÜÇ®Êý
int newTotalMoney = totalMoney; //Ö÷¼üΪ2µÄ¼Ç¼¸ü¸ÄºóµÄÇ®Êý
int totalMoneyChange = oldTotalMoney - newTotalMoney; //×ÜÇ®ÊýµÄ±ä»¯Á¿
string sql = string.Format("update Test1220 set totalMoney = {0},remainMoney = remainMoney-{1} where id = {2}", newTotalMoney, totalMoneyChange, id); //×ÜÇ®Êý±ä»¯£¬Ê£Óà¿ÉÖ§ÅäÇ®ÊýÒ²¸ú×űàºÅ
SqlConnection con = new SqlConnection(sqlConnectString);
con.Open();
SqlCommand cmd = new SqlCommand(sql, con);
cmd.ExecuteNonQuery();
con.Close();
}
CREATE TABLE Test1220(
id int IDENTITY(1,1) NOT NULL PRIMARY KEY,
totalMoney int NULL,
remainMoney int NULL
&n
Ïà¹ØÎĵµ£º
´´½¨×éºÏ²éѯ
¿ÉÓÃUNION²Ù×÷·ûÀ´×éºÏÊýÌõSQL²éѯ¡£ÀûÓÃUNION£¬¿É¸ø³ö¶àÌõSELECTÓï¾ä£¬½«ËüÃǵĽá¹û×éºÏ³Éµ¥¸ö½á¹û¼¯¡£
16.2.1 ʹÓÃUNION
UNIONµÄʹÓúܼòµ¥¡£ËùÐè×öµÄÖ»ÊǸø³öÿÌõSELECTÓï¾ä£¬ÔÚ¸÷ÌõÓï¾äÖ®¼ä·ÅÉϹؼü×ÖUNION¡£
¾ÙÒ»¸öÀý×Ó£¬¼ÙÈçÐèÒª¼Û¸ñСÓÚµÈÓÚ5µÄËùÓÐÎïÆ·µÄÒ»¸öÁÐ±í£¬¶øÇÒ»¹Ïë°üÀ¨¹©Ó¦ÉÌ1001ºÍ1002É ......
ÔÚSQLÓï¾äÓÅ»¯¹ý³ÌÖУ¬ÎÒÃǾ³£»áÓõ½hint,ÏÖ×ܽáÒ»ÏÂÔÚSQLÓÅ»¯¹ý³ÌÖг£¼ûOracle HINTµÄÓ÷¨£º
1. /*+ALL_ROWS*/
±íÃ÷¶ÔÓï¾ä¿éÑ¡Ôñ»ùÓÚ¿ªÏúµÄÓÅ»¯·½·¨,²¢»ñµÃ×î¼ÑÍÌÍÂÁ¿,ʹ×ÊÔ´ÏûºÄ×îС»¯.
ÀýÈç:
SELECT /*+ALL+_ROWS*/ EMP_NO,EMP_NAM,DAT_IN from BSEMPMS WHERE EMP_NO='SCOTT';
2. /*+FIRST_ROWS*/
±íÃ÷¶ÔÓï¾ ......
ÔÚ¼ÆËã»úÖÐÊý¾ÝÓÐÁ½ÖÖÌØÕ÷£ºÀàÐͺͳ¤¶È¡£ËùνÊý¾ÝÀàÐ;ÍÊÇÒÔÊý¾ÝµÄ±íÏÖ·½Ê½ºÍ´æ´¢·½Ê½À´»®·ÖµÄÊý¾ÝµÄÖÖÀà¡£
ÔÚSQL Server ÖÐÿ¸ö±äÁ¿¡¢²ÎÊý¡¢±í´ïʽµÈ¶¼ÓÐÊý¾ÝÀàÐÍ¡£ÏµÍ³ÌṩµÄÊý¾ÝÀàÐÍ·ÖΪ¼¸´óÀ࣬Èç±í4-2 Ëùʾ¡£
ÆäÖУ¬BIGINT¡¢ SQL_VARIANT ºÍTABLE ÊÇSQL Server ......
--Óï ¾ä ¹¦ ÄÜ
--Êý¾Ý²Ù×÷
SELECT --´ÓÊý¾Ý¿â±íÖмìË÷Êý¾ÝÐкÍÁÐ
INSERT --ÏòÊý¾Ý¿â±íÌí¼ÓÐÂÊý¾ÝÐÐ
DELETE --´ÓÊý¾Ý¿â±íÖÐɾ³ýÊý¾ÝÐÐ
UPDATE --¸üÐÂÊý¾Ý¿â±íÖеÄÊý¾Ý
--Êý¾Ý¶¨Òå
CREATE TABLE --´´½¨Ò»¸öÊý¾Ý¿â±í
DROP TABLE --´ÓÊý¾Ý¿âÖÐɾ³ý±í
ALTER TABLE --ÐÞ¸ÄÊý¾Ý¿â±í½á¹¹
CREATE VIEW --´´½¨Ò»¸öÊÓͼ
DRO ......
--Óï ¾ä¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¹¦ ÄÜ
--Êý¾Ý²Ù×÷
SELECT¡¡¡¡¡¡--´ÓÊý¾Ý¿â±íÖмìË÷Êý¾ÝÐкÍÁÐ
INSERT¡¡¡¡¡¡--ÏòÊý¾Ý¿â±íÌí¼ÓÐÂÊý¾ÝÐÐ
DELETE¡¡¡¡¡¡--´ÓÊý¾Ý¿â±íÖÐɾ³ýÊý¾ÝÐÐ
UPDATE¡¡¡¡¡¡--¸üÐÂÊý¾Ý¿â±íÖеÄÊý¾Ý
--Êý¾Ý¶¨Òå
CREATE TABLE¡¡¡¡--´´½¨Ò»¸öÊý¾Ý¿â±í
DROP TABLE¡¡¡¡ --´ÓÊý¾Ý¿âÖÐɾ³ý±í
ALTER ......