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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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INSERT statement conflicted with the FOREIGN KEY constraint - SQL Server
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Alt + F1 is shortcut for sp_help, for futrure readers, select table and press alt + f1
– satsvelke
Jul 16 '19 at 7:00
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Detect iPad Mini in HTML5
...by using these methods.
For the best possible browsing experience, please select what device you are using below.
This choice will be stored for future visits to the website on this device.
[] iPad 2
[*] iPad mini
[] Ancient blackberry device
"
I am not entirely familiar with what you can and...
What is the difference between statically typed and dynamically typed languages?
...t core to the language and usable on demand.
When it comes to technology selection, neither side has an intrinsic superiority over the other. It is just a matter of preference whether you want more control to begin with or flexibility. just pick the right tool for the job, and make sure to check w...
Detect if the app was launched/opened from a push notification
...e case where you have your app in the foreground, lock the phone, and then select a push notification from the lock screen, it is calling didReceiveRemoteNotification:background just before calling applicationWillEnterForeground rather than what we are seeing on iOS 10 where it calls applicationWill...
How to add a custom button state
...tion indicated by @(Ted Hopp) works, but needs a little correction: in the selector, the item states need an "app:" prefix, otherwise the inflater won't recognise the namespace correctly, and will fail silently; at least this is what happens to me.
Allow me to report here the whole solution, with s...
SOAP or REST for Web Services? [closed]
...hod. With SOAP you have the burden of right-clicking on your reference and selecting "update" and then fixing a few compile errors. (Sarcasm included free of charge.)
– Josh M.
Nov 4 '10 at 18:36
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Combining Multiple Commits Into One Prior To Push
...commit: Add feature
b860ddb HEAD@{2}: commit: Add something
Reset to your selected head (I have chosen HEAD@{2})
git reset b860ddb --soft
git status (just to be sure)
Add your new commit
git commit -m "Add new commit"
Note: HEAD@{0} & HEAD@{1} Are now merged into 1 commit, this can be don...
How to see which flags -march=native will activate?
I'm compiling my C++ app using GCC 4.3. Instead of manually selecting the optimization flags I'm using -march=native , which in theory should add all optimization flags applicable to the hardware I'm compiling on. But how can I check which flags is it actually using?
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Bootstrap full-width text-input within inline-form
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The bootstrap docs says about this:
Requires custom widths Inputs, selects, and textareas are 100% wide by
default in Bootstrap. To use the inline form, you'll have to set a
width on the form controls used within.
The default width of 100% as all form elements gets when they got the cl...