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Oracle “Partition By” Keyword
... PARTITION BY clause sets the range of records that will be used for each "GROUP" within the OVER clause.
In your example SQL, DEPT_COUNT will return the number of employees within that department for every employee record. (It is as if you're de-nomalising the emp table; you still return every re...
Setting default permissions for newly created files and sub-directories under a directory in Linux?
...
To get the right ownership, you can set the group setuid bit on the directory with
chmod g+rwxs dirname
This will ensure that files created in the directory are owned by the group. You should then make sure everyone runs with umask 002 or 007 or something of that...
Using Regular Expressions to Extract a Value in Java
...nd in a given string...
if (m.find()) {
// ...then you can use group() methods.
System.out.println(m.group(0)); // whole matched expression
System.out.println(m.group(1)); // first expression from round brackets (Testing)
System.out.println(m.group(2)); // second ...
Regular expression to match standard 10 digit phone number
...-555-1234
Regardless of the way the phone number is entered, the capture groups can be used to breakdown the phone number so you can process it in your code.
Group1: Country Code (ex: 1 or 86)
Group2: Area Code (ex: 800)
Group3: Exchange (ex: 555)
Group4: Subscriber Number (ex: 1234)
Group5: Ext...
Regex: ?: notation (Question mark and colon notation) [duplicate]
...
(?: starts a non-capturing group. It's no different to ( unless you're retrieving groups from the regex after use. See What is a non-capturing group? What does a question mark followed by a colon (?:) mean?.
...
Differences between git remote update and fetch?
... be equivalent to using
git remote update
without specifying any remote group to fetch, and also not having remotes.default set in your repo configuration, and also that none of your remotes have remote.<name>.skipDefaultUpdate set to true.
The current 1.8.3.2 documentation for Git's confi...
python re.sub group: number after \number
...eferences as described above,
\g will use the substring
matched by the group named name, as
defined by the (?P...) syntax.
\g uses the corresponding
group number; \g<2> is therefore
equivalent to \2, but isn’t ambiguous
in a replacement such as \g<2>0. \20
would be inte...
SVG Positioning
...with positioning. I have a series of shapes which are contained in the g group tag. I was hoping to use it like a container, so I could set its x position and then all the elements in that group would also move. But that doesn't seem to be possible.
...
How to concatenate strings of a string field in a PostgreSQL 'group by' query?
I am looking for a way to concatenate the strings of a field within a group by query. So for example, I have a table:
14 An...
Numbering rows within groups in a data frame
...y(df, .(cat), mutate, id = seq_along(val))
or:
library(dplyr)
df %>% group_by(cat) %>% mutate(id = row_number())
or (the most memory efficient, as it assigns by reference within DT):
library(data.table)
DT <- data.table(df)
DT[, id := seq_len(.N), by = cat]
DT[, id := rowid(cat)]
...