Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

LINQ to Entities ʵÏÖsql ¹Ø¼ü×Ö"In"·½Ê½×ܽá

ÔÚLINQ to EntitiesÖÐûÓа취ÔÙÏñ LINQ to SQL ÖÐÒ»ÑùʹÓà Contains µÄ·½·¨À´ÊµÏÖsql "in" ¹Ø¼ü×Ö
ÏÂÃæ´úÂëÔÚ LINQ to SQL ÖпÉÐÐ ÔÚLINQ to EntitiesÈ´ÎÞ·¨ÔËÐУº 
var s = db.Account.Select(c => c.ID);
var ret =(from t in db.Profile
 where s.Contains(t.ID)
 select t).ToList();
Ìæ´ú·½·¨1:ʹÓ÷½·¨Any
var ids=db.Account.Select(c => c.ID);
var ret = (from t in db.Profile where ids.Any(c=>c==t.UserID) select t).ToList();
ʹÓ÷½·¨AnyÌæ»»·¨¸ãÁ˺þö¼Ã»·¨ÊµÏÖÖ±½Ó¶ÔÊý×éAny£¬ÏÂÁдúÂëÈÔÎÞ·¨Ö´ÐУº
int[] ids = new int[]{10101,10005,10007};
var ret = (from t in db.Profile where ids.Any(c=>c==t.UserID) select t).ToList();
ÓÚÊǼÌÐøGoolgeѰÕÒµÚ¶þÖÖ·½·¨£¬ÔÚMSDNÂÛ̳ÉÏÕÒÒ»¸ö¹¹ÔìLambdaÓï¾äµÄ·½·¨
Ìæ´ú·½·¨2:¹¹ÔìLambdaÓï¾ä
        private static Expression<Func<TElement, bool>> BuildWhereInExpression<TElement, TValue>(Expression<Func<TElement, TValue>> propertySelector, IEnumerable<TValue> values)
        {
            ParameterExpression p = propertySelector.Parameters.Single();
            if (!values.Any())
                return e => false;
            var equals = values.Select(value => (Expression)Expression.Equal(propertySelector.Body, Expression.Constant(value, typeof(TValue))));
            var body&


Ïà¹ØÎĵµ£º

±È½ÏÅ£µÄSQL ServerÊé

Microsoft SQL Server2005¼¼ÊõÄÚÄ»:T-SQL³ÌÐòÉè¼Æ
http://www.amazon.cn/mn/detailApp/ref=sr_1_25?_encoding=UTF8&s=books&qid=1261538877&asin=B0011C2568&sr=8-25
Microsoft SQL Server 2005¼¼ÊõÄÚÄ»£º²éѯ¡¢µ÷ÕûºÍÓÅ»¯
http://www.amazon.cn/mn/detailApp/ref=sr_1_4?_encoding=UTF8&s=books&am ......

¡¾Õª¡¿´æ´¢¹ý³Ì±È½Ï¶¯Ì¬SQLµÄÓŵãÔÚÄÄÀï

´æ´¢¹ý³Ì¸ú¶¯Ì¬sqlÏà±ÈÓÐÈçÏÂÓŵ㣺
1¡¢ ´æ´¢¹ý³ÌÔÊÐí±ê×¼×é¼þʽ±à³Ì
´æ´¢¹ý³ÌÔÚ±»´´½¨ÒÔºó¿ÉÒÔÔÚ³ÌÐòÖб»¶à´Îµ÷Óöø²»±ØÖØÐ±àд¸Ã´æ´¢¹ý³ÌµÄSQL
Óï¾ä¶øÇÒÊý¾Ý¿âרҵÈËÔ±¿ÉËæÊ±¶Ô´æ´¢¹ý³Ì½øÐÐÐ޸ĵ«¶ÔÓ¦ÓóÌÐòÔ´´úÂëºÁÎÞÓ°ÏìÒò
ΪӦÓóÌÐòÔ´´úÂëÖ»°üº¬´æ´¢¹ý³ÌµÄµ÷ÓÃÓï¾ä´Ó¶ø¼«´óµØÌá¸ßÁ˳ÌÐòµÄ¿ÉÒÆÖ²ÐÔ
2 ¡¢´æ´¢¹ý³Ì ......

MS SQL 2005Á´½Ó·þÎñÆ÷Á¬½ÓÔ¶³ÌORACLEÈ«¹ý³Ì

µÚÒ»²½:ÏÂÔØ°²×°Oracle 10g Release 2 ¿Í»§¶ËÈí¼þ,ÏÂÔØÁ¬½ÓÊÇ:
http://download.oracle.com/otn/nt/oracle10g/10201/10201_database_win32.zip
ÏÂÔØºó°²×°
 
 
 
µÚ¶þ²½:ÏÂÔØ°²×°Oracle ODAC,ÏÂÔØÁ¬½ÓÊÇ:
http://download.oracle.com/otn/other/ole-oo4o/ODAC1020221.exe
 
µÚÈý²½: ÖØÆôMS SQ ......

sql group by Óë havingµÄÓ÷¨

1. GROUP BY ÊÇ·Ö×é²éѯ, Ò»°ã GROUP BY ÊǺ;ۺϺ¯ÊýÅäºÏʹÓÃ
group by ÓÐÒ»¸öÔ­Ôò,¾ÍÊÇ select ºóÃæµÄËùÓÐÁÐÖÐ,ûÓÐʹÓþۺϺ¯ÊýµÄÁÐ,±ØÐë³öÏÖÔÚ group by ºóÃæ£¨ÖØÒª£©
ÀýÈç,ÓÐÈçÏÂÊý¾Ý¿â±í£º
A    B
1    abc
1    bcd
1    asdfg
 Èç¹ûÓÐÈ ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ