昂贵的左边连接到一个空的子查询？

Question

新手SQL编写者在这里试图更好地理解调度和高效的代码编写。我正在运行一个表现非常差的查询，我不明白为什么。我们正在使用SQL Server 2012。

当我只运行子查询（别名为“te”）时，它在不到一秒的时间内运行并返回零行（我预期的那样）。但是当我运行完整的查询时，它需要花费一分钟的时间。内部联接或左外部联接是否始终返回空集？所以，当子查询没有返回任何结果时，数据库引擎是否应该确定它不需要执行任何这些连接？

有关如何更好地优化的任何建议？在将来编写SQL时，我应该记住哪些最佳实践？

INSERT INTO #target_events
   SELECT p.polyname,
          bp.PurposeAbbr,
          s.schid,
          s.ldate,
          es.EvStrId,
          es.evstrname,
          e.evparent,
          e.evid,
          e.Lat / 1000000.0 AS 'Lat',
          e.Lon / 1000000.0 AS 'Lon',
          e.eta,
          e.etd,
          e.PassOn,
          e.PassOnBoard,
          e.Activity,
          e.SchedStatus,
          e.EvClass
   FROM
   (
       SELECT te.*
       FROM #target_events te
            LEFT OUTER JOIN #target_events te2 ON te2.schid = te.schid
                                                  AND te2.EvStrId = te.EvStrId
                                                  AND te2.EvParent = te.EvParent
                                                  AND te2.Activity != te.Activity
       WHERE te.Activity IN(0, 1)
            AND te.SchedStatus = 3
            AND te2.EvId IS NULL
   ) te -- This subquery runs in under 1 second and returns zero rows
   INNER JOIN events e ON e.schid = te.schid
                          AND e.EvStrId = te.EvStrId
                          AND e.EvParent = te.EvParent
                          AND e.Activity != te.Activity
   INNER JOIN eventstrings es ON es.evstrid = e.evstrid
                                 AND es.schid = e.schid
   INNER JOIN schedules s ON s.schid = e.schid
   LEFT OUTER JOIN clients c ON c.clientid = e.clientid
   LEFT OUTER JOIN address a ON a.addrid = c.clientid
                                AND a.AddrType = 'CH' -- Client Home addresses.
   LEFT OUTER JOIN polygons p ON p.polyid = a.jurispolyid
   LEFT OUTER JOIN booking b ON b.bookingid = e.bookingid
   LEFT OUTER JOIN bookingpurpose bp ON bp.purposeid = b.purposeid; -- These joins take a long time...