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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&


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    SELECT o.name as table_name,c.name AS col_name,type_name(c.xtype) AS type_name,isnull(p.value,'') AS col_Pro ......

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SQLÓÅ»¯¹¤¾ßLecco SQL Expert For Oracle

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1. /*+ALL_ROWS*/ 
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SELECT /*+ALL+_ROWS*/ EMP_NO,EMP_NAM,DAT_IN from BSEMPMS WHERE EMP_NO='SCOTT'; 
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MS SQL 2005Á´½Ó·þÎñÆ÷Á¬½ÓÔ¶³ÌORACLEÈ«¹ý³Ì

µÚÒ»²½:ÏÂÔØ°²×°Oracle 10g Release 2 ¿Í»§¶ËÈí¼þ,ÏÂÔØÁ¬½ÓÊÇ:
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µÚ¶þ²½:ÏÂÔØ°²×°Oracle ODAC,ÏÂÔØÁ¬½ÓÊÇ:
http://download.oracle.com/otn/other/ole-oo4o/ODAC1020221.exe
 
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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£©
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1    bcd
1    asdfg
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