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Does MySQL ignore null values on unique constraints?
... '1' for key 'x'
INSERT table1 VALUES (NULL);
INSERT table1 VALUES (NULL);
SELECT * FROM table1;
Result:
x
NULL
NULL
1
This is not true for all databases. SQL Server 2005 and older, for example, only allows a single NULL value in a column that has a unique constraint.
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Could not change executable permissions on the application
...
I went into the Organizer and selected the Applications underneath my test device. Even though I had deleted the application on my device itself, it still showed up in my list of applications. I deleted it there, and this took care of the issue for me.
...
Difference between .keystore file and .jks file
...t Unity recognizes the former but not the latter when you're navigating to select your keystore file (Unity 2017.3, macOS).
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How do I set the maximum line length in PyCharm?
...ode style->python : ensure right margin is not exceeded. Once this was selected the reformat would work.
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use Winmerge inside of Git to file diff
...GI, which allows you to review the list of files with a difference, before selecting one to examine its internal differences.
I have tweaked it to use only DOS commands
@echo off
setlocal
if "%1" == "-?" (
echo GitDiff - enables diffing of file lists, instead of having to serially
echo d...
Should I use pt or px?
...he terms "uppercase" and "lowercase" which historically had to do with the selection of the fixed typographical characters where the "captital" characters where placed in a box (case) above the non-captitalized characters which were place in a box below, and thus the "lower" case.
There were differ...
best practice to generate random token for forgot password
...es DATETIME,
PRIMARY KEY(id)
);
... you need to add one more column, selector, like so:
CREATE TABLE account_recovery (
id INTEGER(11) UNSIGNED NOT NULL AUTO_INCREMENT
userid INTEGER(11) UNSIGNED NOT NULL,
selector CHAR(16),
token CHAR(64),
expires DATETIME,
PRIMARY K...
How can I decode HTML characters in C#?
...ference to System.Web.dll. Right-click your project in Solution Explorer, select "Add Reference", then browse the list for System.Web.dll.
Now that the reference is added, you should be able to access the method using the fully-qualified name System.Web.HttpUtility.HtmlDecode or insert a using sta...
How do you add an in-app purchase to an iOS application?
...he app you want do add the purchase to
Click the Features header, and then select In-App Purchases on the left
Click the + icon in the middle
For this tutorial, we are going to be adding an in-app purchase to remove ads, so choose non-consumable. If you were going to send a physical item to the user...
How do I move an issue on github to another repo?
...ar, click Transfer issue.
Use the Choose a repository drop-down menu, and select the repository you want to transfer the issue to.
Click Transfer issue.
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