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Is an index needed for a primary key in SQLite?
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It does it for you.
INTEGER PRIMARY KEY columns aside, both UNIQUE and PRIMARY KEY
constraints are implemented by creating an index in the database (in
the same way as a "CREATE UNIQUE INDEX" statement would). Such an
index is used like any other index in the database to optimize
que...
How to check if a variable exists in a FreeMarker template?
...:
[#if userName??]
Hi ${userName}, How are you?
[/#if]
Or with the standard freemarker syntax:
<#if userName??>
Hi ${userName}, How are you?
</#if>
To check if the value exists and is not empty:
<#if userName?has_content>
Hi ${userName}, How are you?
</#if>
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ModelState.AddModelError - How can I add an error that isn't for a property?
...g my database in Create(FooViewModel fvm){...} to see if the fvm.prop1 and fvm.prop2 already exist in that combination; if so, I want to add an error to the modelstate, then return the whole view. I tried:
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How to start nginx via different port(other than 80)
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You have to go to the /etc/nginx/sites-enabled/ and if this is the default configuration, then there should be a file by name: default.
Edit that file by defining your desired port; in the snippet below, we are serving the Nginx instance on port 81.
server {
listen 8...
nginx missing sites-available directory
I installed Nginx on Centos 6 and I am trying to set up virtual hosts. The problem I am having is that I can't seem to find the /etc/nginx/sites-available directory.
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What does the “@” symbol do in Powershell?
... in PowerShell to initialise arrays. What exactly does the @ symbol denote and where can I read more about it?
5 Answers
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How to execute a java .class from the command line
...classpath ( where java looks for .class definitions )
If that's the case and listing the contents of your dir displays:
Echo.java
Echo.class
Then any of this may work:
java -cp . Echo "hello"
or
SET CLASSPATH=%CLASSPATH;.
java Echo "hello"
And later as Fredrik points out you'll get an...
How to suppress Pandas Future warning ?
When I run the program, Pandas gives 'Future warning' like below every time.
3 Answers
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Closing multiple issues in Github with a commit message
...rest of commit message.
The closes clauses can be anywhere in the message and fixes is a valid synonym:
This fixes a memory leak in foo() that closes #4,
also fixes #5 which is a duplicate.
The following used to work, but nowadays only references issues #2 and #3.
Closes #1, #2, #3
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Android - how do I investigate an ANR?
...Application Not Responding). I took a look at the traces.txt file in /data and I see a trace for my application. This is what I see in the trace.
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