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How to select multiple files with ?
How to select multiple files with <input type="file"> ?
9 Answers
9
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What is the dual table in Oracle?
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It's a sort of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
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Cherry pick using TortoiseGit
...y with the target branch checked out.
Use the top-left blue branch name to select the source branch.
Select the commit(s) you want.
Right click and select Cherry Pick this commit.
share
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How to drop columns by name in a data frame
..."z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset function : you can then use the - operator directly on a vector of column names, and you can even omit the quotes around the names !
R> subset(df, select=-c(z,u))
x y
1 1 2
2 2 3
3 3 4
4 4 ...
Group by in LINQ
... p in persons
group p.car by p.PersonId into g
select new { PersonId = g.Key, Cars = g.ToList() };
Or as a non-query expression:
var results = persons.GroupBy(
p => p.PersonId,
p => p.car,
(key, g) => new { PersonId = key, Cars = g.ToList() });
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How to trick an application into thinking its stdout is a terminal, not a pipe
...lt;&- script -qfc "git status" /dev/null | less -R . Those first few characters close stdin for this one commmand.
– Aaron McDaid
Nov 26 '14 at 13:54
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LINQ Using Max() to select a single row
I'm using LINQ on an IQueryable returned from NHibernate and I need to select the row with the maximum value(s) in a couple of fields.
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Where to put include statements, header or source?
...g.
typedef union {
unsigned long l;
unsigned short lw[2];
unsigned char lb[4];
} U_QUAD;
(Yes, I know I'd be in trouble if I moved to a big-endian architecture, but since my compiler doesn't allow anonymous structs in unions, using named identifiers for the bytes within the union would req...
MySQL Query GROUP BY day / month / year
... for added clarity in some cases such as where records span several years. SELECT COUNT(event_id), DATE_FORMAT(event_start, '%Y/%m')
– Ric
Apr 4 '13 at 10:25
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UITableView Cell selected Color?
...f the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothing happens:
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