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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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When restoring a backup, how do I disconnect all active connections?
... the steps (via: Tim Leung)
Right-click the server in Object Explorer and select 'Activity Monitor'.
When this opens, expand the Processes group.
Now use the drop-down to filter the results by database name.
Kill off the server connections by selecting the right-click 'Kill Process' option.
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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...
How do I break a string across more than one line of code in JavaScript?
...n your example, you can break the string into two pieces:
alert ( "Please Select file"
+ " to delete");
Or, when it's a string, as in your case, you can use a backslash as @Gumbo suggested:
alert ( "Please Select file\
to delete");
Note that this backslash approach is not necessarily preferr...
Select first 4 rows of a data.frame in R
How can I select the first 4 rows of a data.frame :
5 Answers
5
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Xcode source automatic formatting
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this shouldn't be selected as the answer. the answer below from @ken is correct
– Ryan Angilly
Feb 8 '13 at 16:44
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How to print from GitHub
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Here's a super simple solution: Simply select all the text in the readme that you want to print, then print and choose "Only selected text".
This worked perfectly in Chrome (including images) and required no javascript or external sites or downloading or buildin...
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...