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How do I use Linq to obtain a unique list of properties from a list of objects?
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IEnumerable<int> ids = list.Select(x=>x.ID).Distinct();
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ComboBox: Adding Text and Value to an Item (no Binding Source)
...ext1";
item.Value = 12;
comboBox1.Items.Add(item);
comboBox1.SelectedIndex = 0;
MessageBox.Show((comboBox1.SelectedItem as ComboboxItem).Value.ToString());
}
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MySQL CONCAT returns NULL if any field contain NULL
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convert the NULL values with empty string by wrapping it in COALESCE
SELECT CONCAT(COALESCE(`affiliate_name`,''),'-',COALESCE(`model`,''),'-',COALESCE(`ip`,''),'-',COALESCE(`os_type`,''),'-',COALESCE(`os_version`,'')) AS device_name
FROM devices
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Does a “Find in project…” feature exist in Eclipse IDE?
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1. Ctrl + H
2. Choose File Search for plain text search in workspace/selected projects
For specific expression searches, choose the relevant tab (such as Java Search which allows you to search for specific identifiers)
For whole project search:
3. Scope (in the form section) > Enclosing...
jQuery - select all text from a textarea
...can I make it so when you click inside a textarea, its entire content gets selected?
6 Answers
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How can i query for null values in entity framework?
...try in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entry.something == value)
select entry;
This is a nasty b...
Hidden Features of Xcode 4
... View > Utilities > Code Snippet Library. To add a new code snippet, select some text in the editor view and drag it into the snippet library. You can either drag a snippet out and drop it in your code to use it, or, much more conveniently, assign a completion shortcut to it.
When you type i...
Get all column names of a DataTable into string array using (LINQ/Predicate)
...es = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
or in LINQ Query syntax:
string[] columnNames = (from dc in dt.Columns.Cast<DataColumn>()
select dc.ColumnName).To...
How to open a web server port on EC2 instance
...asn't immediately clear to me from the linked instructions, but you should select "Custom TCP". Otherwise you won't be able to change the port.
– KKOrange
Dec 12 '19 at 1:39
a...
Possible to perform cross-database queries with PostgreSQL?
... executes a query in a remote database
dblink executes a query (usually a SELECT, but it can be any SQL
statement that returns rows) in a remote database.
When two text arguments are given, the first one is first looked up as
a persistent connection's name; if found, the command is executed on
that...