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What's wrong with nullable columns in composite primary keys?
...ow in a table: when a table has a primary key, you have a guranteed way to select any row from it.
A unique constraint does not necessarily identify every row; it just specifies that if a row has values in its columns, then they must be unique. This is not sufficient to uniquely identify every row...
How do you access a website running on localhost from iPhone browser
...)
Go to the "Info" tab
Click on the drop down menu that says "Wi-Fi" and select "iPhone USB" as shown in the photo.
You'll find an IP address like "xxx.xxx.xx.xx" or similar. Open Safari browser on your iPhone and enter IP_address:port_number
Example: 169.254.72.86:3000
[NOTE: If the IP addr...
Failed to build gem native extension (installing Compass)
...l the Xcode Command Line Tools this is the key to install Compass.
xcode-select --install
Installing the Xcode Command Line Tools are the key to getting Compass working on OS X
3. Install Compass
sudo gem install compass
...
Hide files with certain extension in Sublime Text Editor?
...
Are you talking about the sidebar? For example, if you select File → Open and select a folder, then the folder and its contents are displayed along the left side, allowing you to navigate amongst its contents and sub-directories. If that is the case, then the answer is yes, fi...
Convert seconds to Hour:Minute:Second
...ed to that of the TIME data type, which is from -838:59:59 to 838:59:59 :
SELECT SEC_TO_TIME(8525);
# 02:22:05
See: SEC_TO_TIME
Run the Demo
PostgreSQL example:
SELECT TO_CHAR('8525 second'::interval, 'HH24:MI:SS');
# 02:22:05
Run the Demo
...
How to run SQL script in MySQL?
... If the purpose of writing to file is taking data dump, I guess SELECT ... INTO OUTFILE /path/to/file.csv is more efficient way. See options and syntax here - dev.mysql.com/doc/refman/5.7/en/select-into.html
– Anis
Feb 21 '18 at 6:43
...
jQuery : eq() vs get()
... the DOM elements matched by the jQuery object.
http://api.jquery.com/eq-selector/
Description: Select the element at index n within the matched set.
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How to succinctly write a formula with many variables from a data frame?
...kage leaps and in particular the function regsubsets()
functions for model selection. As stated in the documentation:
Model selection by exhaustive search, forward or backward stepwise, or sequential replacement
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App.Config Transformation for projects which are not Web Projects in Visual Studio?
...="@*|node()">
<xsl:copy>
<xsl:apply-templates select="@*|node()"/>
</xsl:copy>
</xsl:template>
<xsl:template match="/configuration/appSettings">
<xsl:copy>
<xsl:apply-templates select="node()|@*"/>
<xsl:element name="add"&g...
Google App Engine: Is it possible to do a Gql LIKE query?
...e, but you can fake a prefix match using inequality filters:
db.GqlQuery("SELECT * FROM MyModel WHERE prop >= :1 AND prop < :2",
"abc",
u"abc" + u"\ufffd")
This matches every MyModel entity with a string property prop that begins with the characters abc. The unicode ...