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Grouping functions (tapply, by, aggregate) and the *apply family
...er answers) that much of the functionality of the *apply family is covered by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their parti...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
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See the recent answer by @trygvis. Simplest answer by far: REASSIGN OWNED BY old_role [, ...] TO new_role
– David
Dec 4 '12 at 23:39
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Drop all the tables, stored procedures, triggers, constraints and all the dependencies in one sql st
Is there any way in which I can clean a database in SQl Server 2005 by dropping all the tables and deleting stored procedures, triggers, constraints and all the dependencies in one SQL statement?
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Are there best practices for (Java) package organization? [closed]
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I agree package by feature makes the most sense. I heard a great analogy once related to a company office structure. In a layered approach, each of the individuals per level in a company would sit with each other i.e. Executives, managers, a...
Group by & count function in sqlalchemy
I want a "group by and count" command in sqlalchemy. How can I do this?
3 Answers
3
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How to pass parameters correctly?
...cations to that object will be visible to the caller, then you should pass by lvalue reference:
void foo(my_class& obj)
{
// Modify obj here...
}
If your function does not need to modify the original object, and does not need to create a copy of it (in other words, it only needs to observ...
MySQL select 10 random rows from 600K rows fast
...ps, to non-uniform with gaps.
http://jan.kneschke.de/projects/mysql/order-by-rand/
For most general case, here is how you do it:
SELECT name
FROM random AS r1 JOIN
(SELECT CEIL(RAND() *
(SELECT MAX(id)
FROM random)) AS id)
AS r2
WHERE...
How to sort a Ruby Hash by number value?
I have a counter hash that I am trying to sort by count. The problem I am running into is that the default Hash.sort function sorts numbers like strings rather than by number size.
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How to select bottom most rows?
... SELECT TOP 200
columns
FROM
My_Table
ORDER BY
a_column DESC
) SQ
ORDER BY
a_column ASC
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How to Use Order By for Multiple Columns in Laravel 4?
I want to sort multiple columns in Laravel 4 by using the method orderBy() in Laravel Eloquent. The query will be generated using Eloquent like this:
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