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Unique combination of all elements from two (or more) vectors
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Missing in this r-faq overview is the CJ-function from the data.table-package. Using:
library(data.table)
CJ(a, b, unique = TRUE)
gives:
a b
1: ABC 2012-05-01
2: ABC 2012-05-02
3: ABC 2012-05-03
4: ABC 2012-05-04
5: ABC 2012-05-05
6: DEF 2012-05-01
7: DEF 2012-0...
How to check if a process is running via a batch script
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Changing the tasklist format to CSV or anything but table is important because it tasklist default layout (table) truncates long image names which breaks the logic.
– Scott White
Jun 22 '11 at 14:56
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How to Use Order By for Multiple Columns in Laravel 4?
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Is there a way to add an orderBy on an established query?
– Rafael
Jan 16 '15 at 21:43
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How to use multiple AWS Accounts from the command line?
...n the accounts by passing the profile on the command.
$ aws dynamodb list-tables --profile account1
$ aws s3 ls --profile account2
Note:
If you name the profile to be default it will become default profile i.e. when no --profile param in the command.
More on default profile
If you spend mor...
Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
...o which a VARCHAR's length can be extended through the use of online ALTER TABLE. Consequently, I derived those numbers by creating a table with a varchar(2) charset utf8 column and seeing how far I was able to extend it given ALGORITHM=INPLACE.
– antak
Apr 11...
Bootstrap 3 Flush footer to bottom. not fixed
...gt;
</footer>
CSS
html,
body { height: 100%; }
body {
display: table;
width: 100%;
}
.page-row {
display: table-row;
height: 1px;
}
.page-row-expanded { height: 100%; }
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How do I find duplicates across multiple columns?
...V 8.0 introduced "window functions", as seen below (in MySQL 8.0)
CREATE TABLE stuff(
id INTEGER NOT NULL
,name VARCHAR(60) NOT NULL
,city VARCHAR(60) NOT NULL
);
INSERT INTO stuff(id,name,city) VALUES
(904834,'jim','London')
, (904835,'jim','London')
, (90145,'Fred','Paris')
, (9...
UITableView, Separator color where to set?
I have added a UITableView in IB and set the "delegate" and "datasource" and all is working well. What I wanted to do next was change the separator color, but the only way I could find to do this was to add the method to one of the delegate callbacks, is there a better place I should put this?
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Can you do greater than comparison on a date in a Rails 3 search?
... a user_id field. Using the raw SQL notation means you need to include the table clarifications yourself, eg: where("notes.user_id = ?",current_user.id).
– DreadPirateShawn
Jul 13 '14 at 10:03
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Check if at least two out of three booleans are true
... Maybe the poor readability can be compensated by (1) the appropriate table in comment and (2) the appropriate unit test... +1 for something useful learned at school.
– moala
Feb 2 '12 at 15:39
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