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MySQL, better to insert NULL or empty string?
...or an empty string using a bound variable but not for a NULL. This query:
SELECT *
FROM mytable
WHERE mytext = ?
will never match a NULL in mytext, whatever value you pass from the client. To match NULLs, you'll have to use other query:
SELECT *
FROM mytable
WHERE mytext IS NULL
...
LINQ with groupby and count
...(var line in data.GroupBy(info => info.metric)
.Select(group => new {
Metric = group.Key,
Count = group.Count()
})
.OrderBy(x => x.Metric))
{
Console.Wri...
Generate .pem file used to set up Apple Push Notifications
...rtificates" on the left navigation bar. Then, click "+" button.
Step 2: Select Apple Push Notification service SSL (Production) option under Distribution section, then click "Continue" button.
Step 3: Select the App ID you want to use for your BYO app (How to Create An App ID), then click "Con...
How to detect Windows 64-bit platform with .NET?
...
UPDATE: As Joel Coehoorn and others suggest, starting at .NET Framework 4.0, you can just check Environment.Is64BitOperatingSystem.
IntPtr.Size won't return the correct value if running in 32-bit .NET Framework 2.0 on 64-bit Windows (it would return...
Setting PATH environment variable in OSX permanently
...ly solution that works on El Capitan. Better than modifying .bash_profile and .profile.
– IgorGanapolsky
Nov 29 '15 at 21:06
1
...
'App not Installed' Error on Android
...earing all of my cached data. Then, finally I realized all I had to do was select both signature versions when building my signed apk.
Before I only had V2 (Full APK Signature) selected, but after selecting V1 Jar Signature as well, I was able to successfully install my signed APK on my 4.4.2 devic...
What is the difference between Debug and Release in Visual Studio?
...nfig (debug and release). When publishing, we can publish according to our selection in the publish dialog. But, when running application, despite I select Debug, it uses release config (bacause I set debug config in base and debug config), is that normal?
– Jonathan
...
Package doesn't exist error in intelliJ
...ing all modules:
open File > Project Structure...,
go to Modules tab,
select all modules and press the remove button,
then removing all remaining Maven modules from Maven tool window:
select all modules,
right click on them,
press Remove projects,
and then adding them again in Project to...
Node.js project naming conventions for files & folders
What are the naming conventions for files and folders in a large Node.js project?
7 Answers
...
Difference between “on-heap” and “off-heap”
Ehcache talks about on-heap and off-heap memory. What is the difference? What JVM args are used to configure them?
6 Answ...