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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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Auto select file in Solution Explorer from its open tab
...times, I find myself right-clicking on a tab title and searching for Show/Select/Scroll-to this file in Solution Explorer , and I can't find it.
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Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...he query plan that is generated is sub-optimal.
For example, if you send SELECT *
FROM table WHERE id BETWEEN 1 AND
99999999, the DBMS may select a
full-table scan instead of an index
scan because you're grabbing every row
in the table (so sayeth the
statistics). If this is the cached
...
jQuery Validate Plugin - Trigger validation of single field
...he API:
var validator = $( "#myform" ).validate();
validator.element( "#myselect" );
.valid() validates the entire form, as others have pointed out. The API says:
Checks whether the selected form is valid or whether all selected
elements are valid.
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Distinct not working with LINQ to Objects
...ey were hit during the foreach loop. This is because the var temp = books.SelectMany(book => book.Authors).Distinct(); returns an IEnumerable, meaning that the request is not executed right away, it is only executed when the data is used. If you would like an example of this firing right away, ...
How to determine why visual studio might be skipping projects when building a solution
...tion Explorer, right-click the solution > Add > Existing Project and select your project
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Selecting data frame rows based on partial string match in a column
I want to select rows from a data frame based on partial match of a string in a column, e.g. column 'x' contains the string "hsa". Using sqldf - if it had a like syntax - I would do something like:
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What is RemoteSystemsTempFiles in Eclipse?
...s quite simple:
In only 2 steps: install the plug-in then disable it.
select Help -> Install New Software, then choose the "http://download.eclipse.org/releases/[your-version-here]", then enter remote in the filter box.
search for the Remote System Explorer End-User Runtime & co. Probab...
How to Concatenate Numbers and Strings to Format Numbers in T-SQL?
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select 'abcd' + ltrim(str(1)) + ltrim(str(2))
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Xcode : failed to get the task for process
...two Provisioning Profiles for the same name, Xcode5 will only allow you to select one of them. To work around this, you have to use iPhone Configuration Utility to find the Profile you want, find the 30-digit "Profile Identifier" and copy/paste it into the "Other" value of the Provisioning Profile d...