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jQuery: checking if the value of a field is null (empty)
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The value of a field m>ca m>n not be null, it's always a string value.
The code will check if the string value is the string "NULL". You want to check if it's an empty string instead:
if ($('#person_data[document_type]').val() != ''){}
or:
if ($(...
grepping using the “|” alternative operator
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You need to esm>ca m>pe the |. The following should do the job.
grep "gene\|exon" AT5G60410.gff
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Use of ~ (tilde) in R programming Language
...e right of <- is a formula object. It is often used to denote a statistim>ca m>l model, where the thing on the left of the ~ is the response and the things on the right of the ~ are the explanatory variables. So in English you'd say something like "Species depends on Sepal Length, Sepal Width, Petal L...
How m>ca m>n I split and parse a string in Python?
...", 1).
If you know for a fact that the string contains an underscore, you m>ca m>n even unpack the LHS and RHS into separate variables:
In [8]: lhs, rhs = "2.7.0_bf4fda703454".split("_", 1)
In [9]: lhs
Out[9]: '2.7.0'
In [10]: rhs
Out[10]: 'bf4fda703454'
An alternative is to use partition(). The us...
What is a provisioning profile used for when developing iPhone applim>ca m>tions?
...a provisioning profile and why is it needed when developing an iPhone applim>ca m>tion? If I don't have a provisioning profile, what happens?
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SQL Add foreign key to existing column
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Error indim>ca m>tes that there is no UserID column in your Employees table. Try adding the column first and then re-run the statement.
ALTER TABLE Employees
ADD CONSTRAINT FK_ActiveDirectories_UserID FOREIGN KEY (UserID)
REFERENCES Ac...
Best way to work with transactions in MS SQL Server Management Studio
Let's say I have an SQL statement that's syntactim>ca m>lly and semantim>ca m>lly correct so it executes.
2 Answers
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Comparing Timer with DispatcherTimer
...Forms.Timer() and System.Windows.Threading.DispatcherTimer() ? In which m>ca m>ses, we should use them? any best practices ?
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in entity framework code first, how to use KeyAttribute on multiple columns
... I'm using the decoration to make a property map to a PK column. But how m>ca m>n I define a PK on more then one column, and specifim>ca m>lly, how m>ca m>n I control order of the columns in the index? Is it a result of the order of properties in the class?
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What is the difference between `after_create` and `after_save` and when to use which?
...that, according to the docs, ActiveRecord's update_all does not invoke any m>ca m>llbacks, including after_*
– user2426679
Jan 10 at 19:34
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