大约有 43,000 项符合查询结果（耗时：0.0502秒） [XML]
Find rows that have the same value on a column in MySQL
...sses and how many times they're used, with the most used addresses first.
SELECT email,
count(*) AS c
FROM TABLE
GROUP BY email
HAVING c > 1
ORDER BY c DESC
If you want the full rows:
select * from table where email in (
select email from table
group by email having count(*) &g...
What is the error “Every derived table must have its own alias” in MySQL?
...er), which can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn FROM (
SELECT * FROM TT2
) AS T
) AS T
In your case, of course, the entire query could be replaced with:
SELECT ID FROM TT2
...
How do I run Visual Studio as an administrator by default?
...indows 8, 8.1 and 10
In Windows 8, you have to right-click devenv.exe and select "Troubleshoot compatibility".
Select "Troubleshoot program"
Check "The program requires additional permissions"
click "Next", click "Test the program..."
Wait for the program to launch
Click "Next"
Select "Yes, save ...
Removing duplicate rows from table in Oracle
...
Use the rowid pseudocolumn.
DELETE FROM your_table
WHERE rowid not in
(SELECT MIN(rowid)
FROM your_table
GROUP BY column1, column2, column3);
Where column1, column2, and column3 make up the identifying key for each record. You might list all your columns.
...
SQL Server loop - how do I loop through a set of records
how do I loop through a set of records from a select?
8 Answers
8
...
PhpStorm wrap/surround selection?
... to wrap a certain part of text. Is there any shortcut to wrap the current selection, for example:
4 Answers
...
Fastest way to check if a file exist using standard C++/C++11/C?
...r. This does not use many fancy features of C++:
bool is_file_exist(const char *fileName)
{
std::ifstream infile(fileName);
return infile.good();
}
share
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improve this answer
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How do I wrap a selection with an HTML tag in Visual Studio?
...Studio 2015 comes with a new shortcut, Shift+Alt+W, that wraps the current selection with a div. This shortcut leaves the text "div" selected, making it seamlessly changeable to any desired tag. This coupled with the automatic end tag replacement makes for a quick solution.
UPDATE
This shortcut is a...
Finding duplicate values in a SQL table
...
SELECT
name, email, COUNT(*)
FROM
users
GROUP BY
name, email
HAVING
COUNT(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY ...
Only one expression can be specified in the select list when the subquery is not introduced with EXI
...column on the other side of the IN. So the query needs to be of the form:
SELECT * From ThisTable WHERE ThisColumn IN (SELECT ThatColumn FROM ThatTable)
You also want to add sorting so you can select just from the top rows, but you don't need to return the COUNT as a column in order to do your so...