大约有 46,000 项符合查询结果(耗时:0.0298秒) [XML]

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must appear in the GROUP BY clause or be used in an aggregate function

... Yes, this is a common aggregation problem. Before SQL3 (1999), the selected fields must appear in the GROUP BY clause[*]. To workaround this issue, you must calculate the aggregate in a sub-query and then join it with itself to get the additional columns you'd need to show: SELECT m.cname...
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mysql -> insert into tbl (select from another table) and some default values [duplicate]

As the title says, I am trying to insert into one table selecting values from another table and some default values. 5 Ans...
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Using LIMIT within GROUP BY to get N results per group?

...to get all years into a single column, grouped by id and ordered by rate: SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year FROM yourtable GROUP BY id Result: ----------------------------------------------------------- | ID | GROUPED_YEAR |...
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MySQL LIKE IN()?

... might be more efficient, but you'd have to benchmark it to be sure, e.g. SELECT * from fiberbox where field REGEXP '1740|1938|1940'; share | improve this answer | follow ...
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Set selected option of select box

I want to set a option that was selected previously to be displayed on page load. I tried it with the following code: 16 An...
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Select Multiple Fields from List in Linq

... Anonymous types allow you to select arbitrary fields into data structures that are strongly typed later on in your code: var cats = listObject .Select(i => new { i.category_id, i.category_name }) .Distinct() .OrderByDescending(i => i.c...
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PostgreSQL Crosstab Query

... - not fit for missing attributes crosstab(text) with 1 input parameter: SELECT * FROM crosstab( 'SELECT section, status, ct FROM tbl ORDER BY 1,2' -- needs to be "ORDER BY 1,2" here ) AS ct ("Section" text, "Active" int, "Inactive" int); Returns: Section | Active | Inacti...
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how to exclude null values in array_agg like in string_agg using postgres?

... SQL Fiddle select id, (select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users, (select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users from ( SELE...
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MySQL “WITH” clause

... You might be interested in somethinkg like this: select * from ( select * from table ) as Subquery share | improve this answer | follow ...
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MySQL Insert Where query

...INSERT INTO Users(weight, desiredWeight) VALUES (160,145) INSERT using a SELECT statement INSERT INTO Users(weight, desiredWeight) SELECT weight, desiredWeight FROM AnotherTable WHERE id = 1 share | ...