大约有 43,000 项符合查询结果（耗时：0.0418秒） [XML]
Count the occurrences of DISTINCT values
...
SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
share
|
improve this answer
|
...
How to play with Control.Monad.Writer in haskell?
...ype of logNumber is logNumber :: (Show a, Monad m) => a -> WriterT [[Char]] m a for me.
– kmikael
May 27 '15 at 20:15
...
'Java' is not recognized as an internal or external command
...
For Windows 7:
Right click on My Computer
Select Properties
Select Advanced System Settings
Select Advanced tab
Select Environment Variables
Select Path under System Variables
Click on Edit button
In Variable value editor paste this at the start of the line
C:\Progr...
Oracle SQL escape character (for a '&')
... table blah (x varchar(20));
insert into blah (x) values ('blah&amp');
select * from blah;
X
--------------------
blah&amp
share
|
improve this answer
|
...
GROUP BY to combine/concat a column [duplicate]
...
SELECT
[User], Activity,
STUFF(
(SELECT DISTINCT ',' + PageURL
FROM TableName
WHERE [User] = a.[User] AND Activity = a.Activity
FOR XML PATH (''))
, 1, 1, '') AS URL...
A circular reference was detected while serializing an object of type 'SubSonic.Schema .DatabaseColu
...
I think maybe selecting the ones I want may work I think the circular reference is because in Event I have IQueryable<Category> which in turn will have a IQueryable<Event>
– Jon
Jul 20 '09...
Repeat each row of data.frame the number of times specified in a column
...es
library(dplyr)
df %>%
slice(rep(seq_len(n()), freq)) %>%
select(-freq)
# var1 var2
#1 a d
#2 b e
#3 b e
#4 c f
#5 c f
#6 c f
seq_len(n()) part can be replaced with any of the following.
df %>% slice(rep(1:nrow(df), freq)) %>% select(-...
Why am I getting “Cannot Connect to Server - A network-related or instance-specific error”?
...ation
Click on Surface Area Configuration for Services and Connections
Select the instance that is having a problem > Database Engine > Remote Connections
Enable local and remote connections
Restart instance
You may need to create an exception on the firewall for the SQL Server ...
What is the advantage of using heredoc in PHP? [closed]
...e day I used to use them to construct SQL queries:
$sql = <<<SQL
select *
from $tablename
where id in [$order_ids_list]
and product_name = "widgets"
SQL;
To me this has a lower probability of introducing a syntax error than using quotes:
$sql = "
select *
from $tablename
where ...
Xcode 4.4 error - Timed out waiting for app to launch
...
I was trying to debug with a Enterprise Dist cert selected. Switched back to my development cert and the issue was resolved-- thanks!
– RyanG
Nov 19 '12 at 20:15
...