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 ......
SQL²Ù×÷È«¼¯
ÏÂÁÐÓï¾ä²¿·ÖÊÇMssqlÓï¾ä£¬²»¿ÉÒÔÔÚaccessÖÐʹÓá£
SQL·ÖÀࣺ
DDL—Êý¾Ý¶¨ÒåÓïÑÔ(CREATE£¬ALTER£¬DROP£¬DECLARE)
DML—Êý¾Ý²Ù×ÝÓïÑÔ(SELECT£¬DELETE£¬UPDATE£¬INSERT)
DCL—Êý¾Ý¿ØÖÆÓïÑÔ(GRANT£¬REVOKE£¬COMMIT£¬ROLLBACK)
Ê×ÏÈ,¼òÒª½éÉÜ»ù´¡Óï¾ä£º
1¡¢ËµÃ÷£º´´½¨Êý¾Ý¿â
CREATE ......
×î½üÔÚÔÚÒ»µçÁ¦ÏµÍ³£¬ÀïÃæÓõ½±¨±í£¬¾³£ÐèÒª¶ÔSQLÈÕÆÚ½øÐвÙ×÷¡£ÏÖÔÚ½«Ò»Ð©³£ÓõÄSQLÈÕÆÚ²Ù×÷º¯Êý¼ÇÏÂ
/**//**//**//* datepart()º¯ÊýµÄʹÓà ¡¡¡¡
* datepart()º¯Êý¿ÉÒÔ·½±ãµÄÈ¡µ ......
Ò»¡¢»ù´¡
1¡¢ËµÃ÷£º´´½¨Êý¾Ý¿â
CREATE DATABASE database-name
2¡¢ËµÃ÷£ºÉ¾³ýÊý¾Ý¿â
drop database dbname
3¡¢ËµÃ÷£º±¸·Ýsql server
--- ´´½¨±¸·ÝÊý¾ÝµÄ device
USE master
EXEC sp_addumpdevice 'disk', 'testBack', 'c:mssql7backupMyNwind_1.dat'
--- ¿ªÊ¼±¸·Ý
BACKUP DATABASE pubs TO testBack
......
SQLÀïµÄEXISTSÓëin¡¢not existsÓënot in
ϵͳҪÇó½øÐÐSQLÓÅ»¯£¬¶ÔЧÂʱȽϵ͵ÄSQL½øÐÐÓÅ»¯£¬Ê¹ÆäÔËÐÐЧÂʸü¸ß£¬ÆäÖÐÒªÇó¶ÔSQLÖеIJ¿·Öin/not inÐÞ¸ÄΪexists/not exists
Ð޸ķ½·¨ÈçÏ£º
inµÄSQLÓï¾ä
SELECT id, category_id, htmlfile, title, convert(varchar(20),begintime,112) as pubtime
from tab_oa_pub WHERE ......