blocks|key|1042303|text|不能在HAVING之前使用GROUP+BY，HAVING与"WHERE“类似，但对于GROUP+BY条件则是这样。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1042304|entityMap^0|3|6|D|8|M|6|U|5|16|8|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]|$9|O|A|P|B|C]|$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|G|$]]

You can't have a <code>HAVING</code> before a <code>GROUP BY</code>, the <code>HAVING</code> is like the "<code>WHERE</code>" but for the <code>GROUP BY</code> condition.

blocks|key|2089108|text|我最初写道：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2089109|我不确定你的第一次查询是否有效。据我所知，应该总是在小组之后。
|blockquote|2089110|2089111|我被大卫-奥尔德里奇纠正了，甲骨文博士说，命令不重要。虽然出于可读性的原因，我不建议使用Although+(并防止与WHERE子句混淆)，但在技术上是正确的。因此，你的问题的答案是“是的，是一样的”。|2089112|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|K|8|@]|9|@]|A|$]]|$1|E|3|-4|5|6|7|L|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|M|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

I originally wrote:

<blockquote>
 I am not sure your 1st query is valid. As far as I know, HAVING should always come after GROUP BY.
</blockquote>

I was corrected by David Aldridge, the Oracle docs state that the order does not matter. Although I don't recommend using HAVING before GROUP for readability reasons (and to prevent confusion with a WHERE clause), it is technically correct. So that makes the answer to your question 'yes, it's the same'.

blocks|key|2089150|text|这些子句是按顺序计算的。在FROM子句后面可以有一个following子句。在这种情况下，HAVING子句将应用于结果集的整个行。在这种情况下，select列表可能只包含HAVING子句中包含的一个/多个/所有聚合函数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2089151|因此，由于上述原因，您的第一个查询无效。有效的查询将是|2089152|SELECT+SUM(MYTABLE.B)+AS+s+FROM+MYTABLE+
HAVING+SUM(MYTABLE.B)+>+100|code-block|syntax|javascript|2089153|以上查询将返回一行或无行，这取决于是否验证了条件SUM(MYTABLE.B)+>+100。|offset|length|style|CODE|2089154|但是，还有一个原因导致您的第一个查询无效。GROUP+BY子句只能引用其应用的数据集中的列。因此，继续上面的有效查询，您可以编写以下有效查询(尽管它将是无用的和无意义的，因为它应用于任何一行或没有行)：|2089155|SELECT+SUM(s)
FROM+
(
SELECT+SUM(MYTABLE.B)+s
FROM+MYTABLE+
HAVING+SUM(MYTABLE.B)+>+100
)+q
GROUP+BY+s|2089156|所以，我只想回答:不，他们不一样。其中一个甚至是无效的。|2089157|entityMap^0|0|0|0|O|K|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|X|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|Z|8|@$K|10|L|11|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|12|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|13|8|@]|9|@]|A|$G|H]]|$1|S|3|T|5|6|7|14|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|V|$]]

The clauses are evaluated in order. You can have a HAVING clause following immediately the FROM clause. In this case, the HAVING clause will apply to the entire rows of the result set. The select list may only contain, in this case, one/more/all of the aggregation functions contained in the HAVING clause.

So, your first query is not valid because of the above. A valid query would be 

<pre><code>SELECT SUM(MYTABLE.B) AS s FROM MYTABLE 
HAVING SUM(MYTABLE.B) &gt; 100
</code></pre>

The above query will return one or no row, depending on whether the condition <code>SUM(MYTABLE.B) &gt; 100</code> is verified or not.

Still, there is one more reason for which your first query is not valid. The GROUP BY clause may refer only to columns in the data set to which it applies. So going on with my valid query above, you can write the following valid query (though it will be useless and nonsense, as it is applied to either one or no rows):

<pre><code>SELECT SUM(s)
FROM 
(
SELECT SUM(MYTABLE.B) s
FROM MYTABLE 
HAVING SUM(MYTABLE.B) &gt; 100
) q
GROUP BY s
</code></pre>

So, just to answer: no, they're not the same. One of them is not even valid.

blocks|key|2058323|text|正如文献记载的那样，两者之间没有区别。人们只是习惯于看到一群人在一起。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2058324|10002.htm#SQLRF20040|offset|length|2058325|指定where_clause和hierarchical_query_clause后面的GROUP+BY和after。如果同时指定GROUP+BY和can，则它们可以按任一顺序显示。|blockquote|2058326|2058327|http://sqlfiddle.com/#!4/66e33/1|2058328|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/cd/B28359_01/server.111/b28286/statements_10002.htm#SQLRF20040|1^0|0|0|K|0|0|0|0|0|W|1|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@$D|W|E|X|1|Y]]|A|$]]|$1|F|3|G|5|H|7|Z|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|10|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|11|8|@]|9|@$D|12|E|13|1|14]]|A|$]]|$1|L|3|-4|5|6|7|15|8|@]|9|@]|A|$]]]|M|$N|$5|O|P|Q|A|$R|S]]|T|$5|O|P|Q|A|$R|K]]]]

As documented, there is no difference. People are just used to seeing HAVING after GROUP BY.

<a href="http://docs.oracle.com/cd/B28359_01/server.111/b28286/statements_10002.htm#SQLRF20040">http://docs.oracle.com/cd/B28359_01/server.111/b28286/statements_10002.htm#SQLRF20040</a>

<blockquote>
 <blockquote>
 Specify GROUP BY and HAVING after the where_clause and hierarchical_query_clause. If you specify both GROUP BY and HAVING, then they can appear in either order.
 </blockquote>
</blockquote>

<a href="http://sqlfiddle.com/#!4/66e33/1">http://sqlfiddle.com/#!4/66e33/1</a>

blocks|key|2058357|text|允许在查询中施加条件的。差异:对于表中select返回的记录，我们使用WHERE，通过select查询对组返回的组使用HAVING|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2058358|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

both WHERE and HAVING allow for the imposition of conditions in the query. Difference:
We use WHERE for the records returned by select from the table,
We use HAVING for groups returned by group by select query

I have got the table MYTABLE with 2 columns: A and B

I have got the following pieces of the code:

<pre><code>SELECT MYTABLE.A FROM MYTABLE 
 HAVING SUM(MYTABLE.B) &gt; 100
 GROUP BY MYTABLE.A
</code></pre>

and

<pre><code>SELECT MYTABLE.A FROM MYTABLE 
 GROUP BY MYTABLE.A
 HAVING SUM(MYTABLE.B) &gt; 100
</code></pre>

Is it the same? Is it possible that these 2 codes will return diffrent sets of results?

Thank you in advance

Difference between "HAVING ... GROUP BY" and "GROUP BY ... HAVING"

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我得到了表MYTABLE，它有2列：A、和B我得到了以下代码：SELECT MYTABLE.A FROM MYTABLE     HAVING SUM(MYTABLE.B) > 100    GROUP BY MYTABLE.A和SELECT MYTABLE.A FROM MYTABLE     GROUP BY MY...

问“有.组”和“有.组”的区别
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问“有.组”和“有.组”的区别EN