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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...NULL into a column with a NOT NULL constraint.
Inserting a row to a partitioned table, but the values you insert don't map to a partition.
If you use REPLACE, MySQL actually does a DELETE followed by an INSERT internally, which has some unexpected side effects:
A new auto-increment ID is alloc...
Is there a naming convention for MySQL?
... a number at the end of the foreign key name to cater for having more than one referencing column.
Point 5 - I would avoid this. It provides you with little and will become a headache when you want to add or remove columns from a table at a later date.
Some other points are:
Index Naming Convent...
Can you determine if Chrome is in incognito mode via a script?
...
One way is to visit a unique URL and then check to see whether a link to that URL is treated as visited by CSS.
You can see an example of this in "Detecting Incognito" (Dead link).
Research paper by same author to replace D...
Foreign Key to non-primary key
I have a table which holds data, and one of those rows needs to exist in another table. So, I want a foreign key to maintain referential integrity.
...
Creating a URL in the controller .NET MVC
... UrlHelper; there is a .Url property on the controller which will give you one with the correct RequestContext.
– Tobias J
Nov 14 '13 at 15:34
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How do you test functions and closures for equality?
...abstraction
thunks that adjust the actual signature of a function to the one the
function type expects.
https://devforums.apple.com/message/1035180#1035180
This means that you should not even try to compare closures for equality because optimizations may affect the outcome.
...
URLs: Dash vs. Underscore [closed]
...
This is just a guess, but it seems they picked the one that people most probably wouldn't use in a name. This way you can have a name that includes a hyphenated word, and still use the underbar as a word delimiter, e.g. UseTwo-wayLinks could be converted to use_two-way_links...
How to get the number of Characters in a String?
...the blog post "Text normalization in Go"
What is a character?
As was mentioned in the strings blog post, characters can span multiple runes.
For example, an 'e' and '◌́◌́' (acute "\u0301") can combine to form 'é' ("e\u0301" in NFD). Together these two runes are one character.
The definitio...
A monad is just a monoid in the category of endofunctors, what's the problem?
...ote is from Saunders Mac Lane in Categories for the Working Mathematician, one of the foundational texts of Category Theory. Here it is in context, which is probably the best place to learn exactly what it means.
But, I'll take a stab. The original sentence is this:
All told, a monad in X is just a...
What is the difference between `raise “foo”` and `raise Exception.new(“foo”)`?
...cue which will catch RuntimeErrors, report them, and then continue. But in one or two circumstances, we want the daemon to really really die on an error, and in that case we raise an Exception, which goes straight through our "normal error handling code" and out.
And again, if you are writing libra...