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in
±ÈÈçSelect * from t1 where x in ( select y from t2 )
Ö´ÐеĹý³ÌÏ൱ÓÚ:
select *
  from t1, ( select distinct y from t2 ) t2
where t1.x = t2.y;
exists
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for t in ( select * from t1 )
   loop
      if ( exists ( select t2.z from t2 where y = t.x )
      then
         OUTPUT THE RECORD
      end if
end loop
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using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlClient;
using System.Xml;
using System.Data;
namespace MyDbTest
{
class Program
{
static void Main(string[] args)
{
SqlConnection thisConnection = new SqlConnection(
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EXEC sp_configure 'show advanced options', 1
RECONFIGURE
EXEC sp_configure 'xp_cmdshell', 1
RECONFIGURE
/** µ¼³öÎı¾Îļþ 
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