q****g
发帖数: 12 | 1 我用jdbc操作 sql server下的 database时，
遇到一个奇怪的现象：比如说一个简单的语句：
SELECT id, attr
INTO tempTB
FROM TB
WHERE (...)
ORDER BY attr
返回的tempTB 有的时候根本不是按照attr排序的，
确切地说，只是部分排序。比如说如果数据范围[1，1000]，
输出的结果可能是 992 993,...1000, 876，877，878，。。
我多run几次，有时候又能输出正确排序后的结果。
有人遇到过这种情况么？到底怎么回事啊？
难道是sql server安装有问题？
但是我的机器刚刚重装过，以前用这个sql server的安装文件
也装过，从来没有碰到过这种问题。 | k***e
发帖数: 12 | 2 When select from tempTB, you need to use order by attr to gurantee the
returned result is ordered. | q****g
发帖数: 12 | 3 Thanks!I've also found the reason from the website,
order by在select into 或者insert里面都是没用/unpredictable的:
Tables do not have an order. In other words, tables by definition are
logically an unordered set of rows. Using ORDER BY in a INSERT...SELECT or
SELECT...INTO does not mean that the data in the table is 'ordered'. The
order of rows which you see when you do a SELECT without an ORDER BY clause
is a undefined/arbitrary order chosen by the optimizer based on the physical
characteristics, indexes,
【在 k***e 的大作中提到】
: When select from tempTB, you need to use order by attr to gurantee the
: returned result is ordered.
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