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Select distinct using linq [duplicate]
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myList.GroupBy(test => test.id)
.Select(grp => grp.First());
Edit: as getting this IEnumerable<> into a List<> seems to be a mystery to many people, you can simply write:
var result = myList.GroupBy(test => test.id)
.S...
Random record from MongoDB
...llection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
{ $match: { a:...
Open directory dialog
I want the user to select a directory where a file that I will then generate will be saved. I know that in WPF I should use the OpenFileDialog from Win32, but unfortunately the dialog requires file(s) to be selected - it stays open if I simply click OK without choosing one. I could "hack up" the f...
Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
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How to get full path of selected file on change of using javascript, jquery-ajax
How to get full path of file while selecting file using <input type=‘file’>
11 Answers
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NULL values inside NOT IN clause
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Query A is the same as:
select 'true' where 3 = 1 or 3 = 2 or 3 = 3 or 3 = null
Since 3 = 3 is true, you get a result.
Query B is the same as:
select 'true' where 3 <> 1 and 3 <> 2 and 3 <> null
When ansi_nulls is on, 3 <&...
How can I get enum possible values in a MySQL database?
... This solution works on codeigniter github.com/thiswolf/codeigniter-enum-select-boxes
– You Know Nothing Jon Snow
Jul 7 '13 at 16:28
3
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MySQL ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)
...=/tmp/mysql-5.5.sock
Welcome to the MySQL monitor (...)
mysql> SELECT user, host FROM mysql.user;
+------+-----------+
| user | host |
+------+-----------+
| bill | % |
| root | 127.0.0.1 |
| root | ::1 |
| root | localhost |
+------+---...
How to select lines between two marker patterns which may occur multiple times with awk/sed
Using awk or sed how can I select lines which are occurring between two different marker patterns? There may be multiple sections marked with these patterns.
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django models selecting single field
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thanks for the answer, what if I want to select only 1 or more fields (not all)?
– zentenk
Sep 21 '11 at 16:42
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