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MySQL SELECT only not null values
...
You should use IS NOT NULL. (The comparison operators = and <> both give UNKNOWN with NULL on either side of the expression.)
SELECT *
FROM table
WHERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality op...
Prevent RequireJS from Caching Required Scripts
...=" + (new Date()).getTime() for automatic cache-busting during development and urlArgs: "bust=v2" for production where I increment the hard-coded version num after rolling out an updated required script.
– BumbleB2na
Dec 16 '11 at 15:44
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arrow operator (->) in function heading
...declaration:
return-type identifier ( argument-declarations... )
and
auto identifier ( argument-declarations... ) -> return_type
They are equivalent. Now when they are equivalent, why do you ever want to use the latter? Well, C++11 introduced this cool decltype thing that lets...
Reading GHC Core
...re is GHC's intermediate language. Reading Core can help you better understand the performance of your program. Someone asked me for documentation or tutorials on reading Core, but I couldn't find much.
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Can I find out the return value before returning while debugging in Intellij?
...oint on Object method(){ . This will allow you to watch for the entrance and exit of the method. I believe you have to use this in conjunction with "Watch method return values" like stated above, but I haven't been able to completely test this as it takes too long to compute. Beware, this does dr...
How to do associative array/hashing in JavaScript
...h new Array() is frowned up. The article eventually mentions its drawbacks and suggests new Object() or {} as preferred alternatives, but that's near the end and I fear most readers won't get that far.
– Daniel Lubarov
May 16 '15 at 5:55
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Authenticate Jenkins CI for Github private repository
...h that task.. Tried the documentation, generating ssh-key for jenkins user and all what I can see is: "unable to clone the repo". I've checked URLs - they are valid.
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Create PostgreSQL ROLE (user) if it doesn't exist
...sword';
END IF;
END
$do$;
(Building on @a_horse_with_no_name's answer and improved with @Gregory's comment.)
Unlike, for instance, with CREATE TABLE there is no IF NOT EXISTS clause for CREATE ROLE (up to at least pg 12). And you cannot execute dynamic DDL statements in plain SQL.
Your reques...
Getting value of HTML Checkbox from onclick/onchange events
From within onClickHandler and/or onChangeHandler , how can I determine what is the new state of the checkbox?
3 Answers...
How to parse a string into a nullable int
...eturn null;
}
Edit @Glenn int.TryParse is "built into the framework". It and int.Parse are the way to parse strings to ints.
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