SELECT T1.Col1, T1.Col2, S2.T1.Col2, S2.T1.Col3
FROM T1
INNER JOIN S2.T1 ON S2.T1.Col1 = S1.T1.Col1

Select(Col1.Of(T1),Col2.Of(T1),Col2.Of(T2),Col3.Of(T2))
.From(T1)
.InnerJoin(S2.T1).As(T2).On(Col1.Of(T2) == Col1.Of(T1))

#include <Core/Core.h>
#include <plugin/sqlite3/Sqlite3.h>

using namespace Upp;

CONSOLE_APP_MAIN
{
	Sqlite3Session sqlite3;
	
	sqlite3.SetTrace();
	
	SQL = sqlite3;

	SqlId T1("T1"), Col1("Col1"), Col2("Col2");
	SQLID(T2); SQLID(S2);

	SQL * Select(T1(Col1), T1(Col2), T2(Col2), T2(Col2))
	      .From(T1)
	      .InnerJoin(S2(T1).As(T2))
	      .On(T2(Col1) == T1(Col2));
}

select T1.Col1, T1.Col2, T2.Col2, T2.Col2 from T1 inner join S2.T1 T2 on T2.Col1 = T1.Col2