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IN vs OR in the SQL WHERE Clause
...xed I got these results:
SELECT COUNT(*) FROM t_inner WHERE val IN (1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000);
1 row fetched in 0.0032 (1.2679 seconds)
SELECT COUNT(*) FROM t_inner WHERE val = 1000 OR val = 2000 OR val = 3000 OR val = 4000 OR val = 5000 OR val = 6000 OR val = 7000 OR v...
Rails check if yield :area is defined in content_for
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217
@content_for_whatever is deprecated.
Use content_for? instead, like this:
<% if content_fo...
How to compute the similarity between two text documents?
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array([[1. , 0.17668795, 0.27056873, 0. , 0. ],
[0.17668795, 1. , 0.15439436, 0. , 0. ],
[0.27056873, 0.15439436, 1. , 0.19635649, 0.16815247],
[0. , 0. , 0.19635649, 1. ...
How to count the number of occurrences of an element in a List
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In Git, what is the difference between origin/master vs origin master?
...table
You can merge multiple branches...
git merge origin/master hotfix-2275 hotfix-2276 hotfix-2290
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What are Scala context and view bounds?
...The most common usage of view bounds in the standard library (before Scala 2.8.0, anyway), is with Ordered, like this:
def f[A <% Ordered[A]](a: A, b: A) = if (a < b) a else b
Because one can convert A into an Ordered[A], and because Ordered[A] defines the method <(other: A): Boolean, I ...
Create PostgreSQL ROLE (user) if it doesn't exist
...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 request to "avoid PL/pgSQL" is impossible except by using another PL. The DO statement uses plpgsql as default procedural language. The syntax allows to om...
What is & used for
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answered Jan 31 '12 at 17:40
QuentinQuentin
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What is cardinality in MySQL?
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Max cardinality: All values are unique
Min cardinality: All values are the same
Some columns ...