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How to check a not-defined variable in JavaScript
...lejandroSilva Sorry for late reply. That won't work since typeof returns a string, so it will return 'undefined' for an undefined variable, which in turn will evaluate as TRUE therefore leading to a false positive of a defined var.
– Dmitri Farkov
Mar 17 '15 at...
WPF: Setting the Width (and Height) as a Percentage Value
...
I already tried that, but I'm getting this error: '2*' string cannot be converted to Length.'
– Andreas Grech
Apr 4 '09 at 16:06
6
...
Do I need to create indexes on foreign keys on Oracle?
I have a table A and a table B . A has a foreign key to B on B 's primary key, B_ID .
7 Answers
...
How do you use script variables in psql?
...ient:
... If you want to use the variable as the value in a conditional string query, such as ...
SELECT * FROM table1 WHERE column1 = ':myvariable';
... then you need to include the quotes in the variable itself as the above will not work. Instead define your variable as such ...
\set myvar...
File input 'accept' attribute - is it useful?
... be an
ASCII case-insensitive
match for one of the following:
The string audio/*
Indicates that sound files are accepted.
The string video/*
Indicates that video files are accepted.
The string image/*
Indicates that image files are accepted.
A...
SQL Server: SELECT only the rows with MAX(DATE)
...o join on a query, as per Cularis' answer.
Alternatively, the most simple and straight forward way is a correlated-sub-query in the WHERE clause.
SELECT
*
FROM
yourTable AS [data]
WHERE
DateEntered = (SELECT MAX(DateEntered) FROM yourTable WHERE orderNo = [data].orderNo)
Or...
WHERE
ID ...
How to Update Multiple Array Elements in mongodb
...1243
As a work around you can:
Update each item individually
(events.0.handled events.1.handled
...) or...
Read the document, do the edits
manually and save it replacing the
older one (check "Update if
Current" if you want to ensure
atomic updates)
...
Sort ArrayList of custom Objects by property
...s people used compareTo which according to some research is a method for Strings.
29 Answers
...
Why does MSBuild look in C:\ for Microsoft.Cpp.Default.props instead of c:\Program Files (x86)\MSBui
...o locate default cpp properties but cannot because the registry lacks this String Value.
Check for the String Value
Launch regedit
Navigator to HKLM\SOFTWARE\Microsoft\MSBuild\ToolsVersions\4.0
Inspect VCTargetsPath key. The value should = "$(MSBuildExtensionsPath32)\Microsoft.Cpp\v4.0\"
T...
MySQL Orderby a number, Nulls last
... syntax to sort nulls last. Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A go...