LINQ to Entities ʵÏÖsql ¹Ø¼ü×Ö"In"·½Ê½×ܽá
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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();
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int[] ids = new int[]{10101,10005,10007};
var ret = (from t in db.Profile where ids.Any(c=>c==t.UserID) select t).ToList();
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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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1. /*+ALL_ROWS*/
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SELECT /*+ALL+_ROWS*/ EMP_NO,EMP_NAM,DAT_IN from BSEMPMS WHERE EMP_NO='SCOTT';
2. /*+FIRST_ROW ......
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http://download.oracle.com/otn/nt/oracle10g/10201/10201_database_win32.zip
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http://download.oracle.com/otn/other/ole-oo4o/ODAC1020221.exe
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