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
À´Ô´:SQL°ïÖúÎĵµ
CASE
¼ÆËãÌõ¼þÁÐ±í²¢·µ»Ø¶à¸ö¿ÉÄܽá¹û±í´ïʽ֮һ¡£
CASE ¾ßÓÐÁ½ÖÖ¸ñʽ£º
¼òµ¥ CASE º¯Êý½«Ä³¸ö±í´ïʽÓëÒ»×é¼òµ¥±í´ïʽ½øÐбȽÏÒÔÈ·¶¨½á¹û¡£
CASE ËÑË÷º¯Êý¼ÆËãÒ»×é²¼¶û±í´ïʽÒÔÈ·¶¨½á¹û¡£
Á½ÖÖ¸ñʽ¶¼Ö§³Ö¿ÉÑ¡µÄ ELSE ²ÎÊý¡£
Óï·¨
¼òµ¥ CASE º¯Êý£º
CASE input_expression
&n ......
#region µÃµ½ËùÓб¾µØÍøÂçÖпÉʹÓõÄSQL·þÎñÆ÷Áбí
/// <summary>
/// µÃµ½ËùÓб¾µØÍøÂçÖпÉʹÓõÄSQL·þÎñÆ÷Áбí
/// </summary>
/// <param name="p_strServerList">·þÎñÆ÷Áбí</param& ......
SQL ×¢Èë¹¥»÷ÔÀí¼°·À»¤
ÔÚÈ·ÈÏ¿ÉÒÔ×¢ÈëµÄÇé¿öÏ£¬Ê¹ÓÃÏÂÃæµÄÓï¾ä£º
HTTP://www.163.com/news.asp?id=xx ;and (select count(*) from sysobjects)£¾0
HTTP://www.163.com/news.asp?id=xx ;and (select count(*) from msysobjects)£¾0
Èç¹ûÊý¾Ý¿âÊÇSQLServer£¬ÄÇôµÚÒ»¸öÍøÖ·µÄÒ³ÃæÓëÔÒ³ÃæHTTP://www.163.com/news.asp? ......
·½·¨Ò»
µÚÒ»²½£ºµÇÈësql/plus Ö´ÐÐÃüÁÎÞÏȺó˳Ðò£©
set time on; (˵Ã÷£º´ò¿ªÊ±¼äÏÔʾ£©
set autotrace on; (˵Ã÷£º´ò¿ª×Ô¶¯·ÖÎöͳ¼Æ£¬²¢ÏÔʾSQLÓï¾äµÄÔËÐнá¹û£©
set autotrace traceonly; (˵à ......