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Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);
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Why can't the C# constructor infer type?
...type inference?
No. When you have
new Foo(bar)
then we could identify all types called Foo in scope regardless of generic arity, and then do overload resolution on each using a modified method type inference algorithm. We'd then have to create a 'betterness' algorithm that determines which of t...
Lock Escalation - What's happening here?
... to take fewer, larger locks (e.g. entire table) instead of locking many smaller things (e.g. row locks).
But this can be problematic when you have a huge table, because taking a lock on the entire table may lock out other queries for a long time. That's the tradeoff: many small-granularity locks...
Get current value of a setting in Vim
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If you don't remember what setting you want to check, you can view all settings:
:set all
or show each setting, one setting per line:
:set! all
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CSS “and” and “or”
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Are we really still concerned with supporting older versions of IE in 2018? Not even Microsoft does.
– Anomaly
Mar 15 '18 at 12:18
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chrome undo the action of “prevent this page from creating additional dialogs”
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No. But you should really use console.log() instead of alert() for debugging.
In Chrome it even has the advantage of being able to print out entire objects (not just toString()).
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What's an object file in C?
...t from the compilation phase. It's mostly machine code, but has info that allows a linker to see what symbols are in it as well as symbols it requires in order to work. (For reference, "symbols" are basically names of global objects, functions, etc.)
A linker takes all these object files and comb...
How to process POST data in Node.js?
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The functionality is actually in the BodyParser module in connect, if you want to use a lower level entry point.
– Julian Birch
Jun 20 '11 at 6:59
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Use PHP composer to clone git repo
I'm trying to use composer to automatically clone a git repository from github that isn't in packagist but it's not working and I can't figure out what am I doing wrong.
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How to sync with a remote Git repository?
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Generally git pull is enough, but I'm not sure what layout you have chosen (or has github chosen for you).
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