大约有 44,000 项符合查询结果(耗时:0.0435秒) [XML]
Split column at delimiter in data frame [duplicate]
...OO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.frame:
within(df, FOO<-data.frame(do.call('rbind', strsplit(as.character(FOO), '|', fixed=TRUE))))
Which produces:
ID ...
Is there a float input type in HTML5?
...Elfayer's edit: quotes are optional in HTML unless you want to use certain characters. Personally I prefer to omit them where possible for better readability.
– Dave
Apr 2 '14 at 10:02
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How do I find duplicates across multiple columns?
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Duplicated id for pairs name and city:
select s.id, t.*
from [stuff] s
join (
select name, city, count(*) as qty
from [stuff]
group by name, city
having count(*) > 1
) t on s.name = t.name and s.city = t.city
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PHP best way to MD5 multi-dimensional array?
...) function.
Test results for multi-dimensional array with md5-hashes (32 char) in keys and values:
Test name Repeats Result Performance
serialize 10000 0.761195 sec +0.00%
print_r 10000 1.669689 sec -119.35%
json_encode 10000...
How to extract the first two characters of a string in shell scripting?
...{long:0:2}" ; echo "${short}"
US
This will set short to be the first two characters of long. If long is shorter than two characters, short will be identical to it.
This in-shell method is usually better if you're going to be doing it a lot (like 50,000 times per report as you mention) since there...
How do you do a limit query in JPQL or HQL?
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// SQL: SELECT * FROM table LIMIT start, maxRows;
Query q = session.createQuery("FROM table");
q.setFirstResult(start);
q.setMaxResults(maxRows);
share
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SQL Update with row_number()
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One more option
UPDATE x
SET x.CODE_DEST = x.New_CODE_DEST
FROM (
SELECT CODE_DEST, ROW_NUMBER() OVER (ORDER BY [RS_NOM]) AS New_CODE_DEST
FROM DESTINATAIRE_TEMP
) x
share
|
im...
Bootstrap 3: Keep selected tab on page refresh
I am trying to keep selected tab active on refresh with Bootstrap 3 . Tried and checked with some question already been asked here but none of work for me. Don't know where I am wrong. Here is my code
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MySQL Orderby a number, Nulls last
...Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://t...
Using column alias in WHERE clause of MySQL query produces an error
... though, by putting the expression directly into the WHERE x IN y clause:
SELECT `users`.`first_name`,`users`.`last_name`,`users`.`email`,SUBSTRING(`locations`.`raw`,-6,4) AS `guaranteed_postcode`
FROM `users` LEFT OUTER JOIN `locations`
ON `users`.`id` = `locations`.`user_id`
WHERE SUBSTRING(`loca...