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How to do the equivalent of pass by reference for primitives in Java
...ment " + toy.toyNumber);
}
Choice 2: return the value instead of pass by reference
int play(int toyNumber){
System.out.println("Toy number in play " + toyNumber);
toyNumber++;
System.out.println("Toy number in play after increement " + toyNumber);
return toyNumber
}
...
How to use GROUP_CONCAT in a CONCAT in MySQL
..., ':', group_concat(`Value` separator ',')) as `Name`
from mytbl
group by
id,
`Name`
) tbl
group by id;
You can see it implemented here : Sql Fiddle Demo. Exactly what you need.
Update
Splitting in two steps. First we get a table having all values(comma separated) against a unique[N...
Assign multiple columns using := in data.table, by group
...
f <- function(x) {list("hi", "hello")}
x[ , c("col1", "col2") := f(), by = a][]
# a b col1 col2
# 1: 1 1 hi hello
# 2: 2 2 hi hello
# 3: 3 3 hi hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 c...
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
...N
(SELECT home, MAX(datetime) AS MaxDateTime
FROM topten
GROUP BY home) groupedtt
ON tt.home = groupedtt.home
AND tt.datetime = groupedtt.MaxDateTime
share
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improve this answer
...
How to select the rows with maximum values in each group with dplyr? [duplicate]
...
Try this:
result <- df %>%
group_by(A, B) %>%
filter(value == max(value)) %>%
arrange(A,B,C)
Seems to work:
identical(
as.data.frame(result),
ddply(df, .(A, B), function(x) x[which.max(x$value),])
)
#[1] TRUE
As pointed ...
Window Features - 更多技术 - 清泛网 - 专注C/C++及内核技术
... window used as a main window typically includes all of these components.
By specifying the WS_OVERLAPPED or WS_OVERLAPPEDWINDOW style in the CreateWindowEx function, an application creates an overlapped window. If you use the WS_OVERLAPPED style, the window has a title bar and border. If you use t...
Difference between filter and filter_by in SQLAlchemy
Could anyone explain the difference between filter and filter_by functions in SQLAlchemy?
Which one should I be using?
...
How to get next/previous record in MySQL?
...e records with IDs 3,4,7,9 and I want to be able to go from one to another by navigation via next/previous links. The problem is, that I don't know how to fetch record with nearest higher ID.
...
SQL Server 2008: How to query all databases sizes?
...
I don't know exactly what you mean by efficiency but this is straightforward and it works for me:
SELECT
DB_NAME(db.database_id) DatabaseName,
(CAST(mfrows.RowSize AS FLOAT)*8)/1024 RowSizeMB,
(CAST(mflog.LogSize AS FLOAT)*8)/1024 LogSizeMB,
...
Function to Calculate Median in SQL Server
...
SELECT AVG(1.0 * val)
FROM (
SELECT val FROM dbo.EvenRows
ORDER BY val
OFFSET (@c - 1) / 2 ROWS
FETCH NEXT 1 + (1 - @c % 2) ROWS ONLY
) AS x;
Of course, just because one test on one schema in 2012 yielded great results, your mileage may vary, especially if you're on SQL Server...