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Django filter queryset __in for *every* item in list
Let's say I have the following models
6 Answers
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scopes with lambda and arguments in Rails 4 style?
I'm wondering how the following is done in Rails 4 or if I just use the Rails 3 approach for using a lambda that can pass an argument the same way with 4 as I do with 3.
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ORDER BY the IN value list
I have a simple SQL query in PostgreSQL 8.3 that grabs a bunch of comments. I provide a sorted list of values to the IN construct in the WHERE clause:
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MySQL select 10 random rows from 600K rows fast
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A great post handling several cases, from simple, to gaps, 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...
When to add what indexes in a table in Rails
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Should I add "index" to all the foreign keys like "xxx_id"?
It would be better, because it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be c...
SQL query to find record with ID not in another table
I have two tables with binding primary key in database and I desire to find a disjoint set between them. For example,
6 Ans...
Filter dataframe rows if value in column is in a set list of values [duplicate]
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Use the isin method:
rpt[rpt['STK_ID'].isin(stk_list)]
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Possible to do a MySQL foreign key to one of two possible tables?
...problem I have three tables; regions, countries, states. Countries can be inside of regions, states can be inside of regions. Regions are the top of the food chain.
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Does the join order matter in SQL?
Disregarding performance, will I get the same result from query A and B below? How about C and D?
4 Answers
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How to jQuery clone() and change id?
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// Read the Number from that DIV's ID (i.e: 3 from "klon3")
// And increment that number by 1
var num = parseInt( $div.prop("id").match(/\d+/g), 10 ) +1;
// Clone it and assign the new ID (i.e: from num 4 to ID "klon4")
var $klon = $div.clone().prop('id', 'klon'+num );
// Fin...