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SQL WHERE ID IN (id1, id2, …, idn)
...column name lots of times; additionally the SQL engine doesn't immediately know that you want to check if the value is one of the values in a fixed list. However, a good SQL engine could optimize it to have equal performance like with IN. There's still the readability issue though...
Option 3 is sim...
T-SQL: Selecting rows to delete via joins
... ON b.Bid = a.Bid
AND [my filter condition]
should work
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How to output numbers with leading zeros in JavaScript [duplicate]
...ly outdated. ECMAScript 2017 includes String.prototype.padStart
You're asking for zero padding? Not really rounding. You'll have to convert it to a string since numbers don't make sense with leading zeros. Something like this...
function pad(num, size) {
var s = num+"";
while (s.length &l...
How to update a single library with Composer?
I need to install only 1 package for my SF2 distribution (DoctrineFixtures).
8 Answers
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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Signed integer overflow (as strictly speaking, there is no such thing as "unsigned integer overflow") means undefined behaviour. And this means anything can happen, and discussing why does it happen under the rules of C++ doesn't make sense.
C++11 draft N3337: §5....
What's the proper way to install pip, virtualenv, and distribute for Python?
...alenv:
http://pypi.python.org/pypi/virtualenv
https://pypi.python.org/packages/source/v/virtualenv/virtualenv-12.0.7.tar.gz
(or whatever is the latest version!)
Unpack the source tarball
Use the unpacked tarball to create a clean virtual environment. This virtual environment will be used to "boot...
How to calculate number of days between two given dates?
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DanaDana
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What's the difference between array_merge and array + array?
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The difference is:
The + operator takes the union of the two arrays, whereas the array_merge function takes the union BUT the duplicate keys are overwritten.
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MySQL DISTINCT on a GROUP_CONCAT()
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Daniel Vassallo
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answered Jun 21 '10 at 9:41
NaktibaldaNakti...
Adding a column to an existing table in a Rails migration
... (rails generate migration add_email_to_users email:string will do the trick).
It will create a migration file containing line:
add_column :users, email, string
Then do a rake db:migrate and it'll run the new migration, creating the new column.
If you have not yet run the original migration you can...