大约有 48,000 项符合查询结果（耗时：0.0294秒） [XML]
Is there any difference between GROUP BY and DISTINCT
...s stated; the SQL Server is smart enough to realize that if you are using "Group By" and not using any aggregate functions, then what you actually mean is "Distinct" - and therefore it generates an execution plan as if you'd simply used "Distinct."
However, I think it's important to note Hank's res...
Tablix: Repeat header rows on each page not working - Report Builder 3.0
...x structure you are using. In a table, for example, you do not have column groups, so Reporting Services does not recognize which textboxes are the column headers and setting RepeatColumnHeaders property to True doesn't work.
Instead, you need to:
Open Advanced Mode in the Groupings pane. (Click ...
Using Linq to group a list of objects into a new grouped list of list of objects
...
var groupedCustomerList = userList
.GroupBy(u => u.GroupID)
.Select(grp => grp.ToList())
.ToList();
share
|
...
Replace specific characters within strings
...
With a regular expression and the function gsub():
group <- c("12357e", "12575e", "197e18", "e18947")
group
[1] "12357e" "12575e" "197e18" "e18947"
gsub("e", "", group)
[1] "12357" "12575" "19718" "18947"
What gsub does here is to replace each occurrence of "e" with an ...
Linux, Why can't I write even though I have group permissions?
I want to create a file in a directory owned by the staff group which I am a member of. Why can I not do this?
6 Answers
...
Regex Named Groups in Java
...nderstanding that the java.regex package does not have support for named groups ( http://www.regular-expressions.info/named.html ) so can anyone point me towards a third-party library that does?
...
How to use GROUP BY to concatenate strings in MySQL?
...
SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string result with th...
How do I get the name of captured groups in a C# Regex?
Is there a way to get the name of a captured group in C#?
5 Answers
5
...
Regex group capture in R with multiple capture-groups
In R, is it possible to extract group capture from a regular expression match? As far as I can tell, none of grep , grepl , regexpr , gregexpr , sub , or gsub return the group captures.
...
SQL - HAVING vs. WHERE
...ation) hence HAVING works correctly.
As a rule of thumb, use WHERE before GROUP BY and HAVING after GROUP BY. It is a rather primitive rule, but it is useful in more than 90% of the cases.
While you're at it, you may want to re-write your query using ANSI version of the join:
SELECT L.LectID, Fn...