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Why do we need tuples in Python (or any immutable data type)?
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@ACoolie, that's totally dominated by the random calls (try doing just that, you'll see!), so not very significant. Try python -mtimeit -s "x=23" "[x,x]" and you'll see a more meaningful speedup of 2-3 times for building the tuple vs building the list.
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How to properly create composite primary keys - MYSQL
...xing purposes then correct? As in I wouldn't be able to reference a record by using this composite, I would still have to so do an UPDATE info ... WHERE t1ID=11209 AND t2ID=437 ?
– filip
Apr 29 '11 at 20:28
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Combine two ActiveRecord::Relation objects
... I did this:
name_relation = first_name_relation + last_name_relation
Ruby 1.9, rails 3.2
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Add a column to existing table and uniquely number them on MS SQL Server
...to add a column to an existing legacy database and write a procedure by which I can assign each record a different value. Something like adding a column and autogenerate the data for it.
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How to force use of overflow menu on devices with menu button
...wer for the situation of physical menu button.
This is actually prevented by design. According to the Compatibility Section of the Android Design Guide,
"...the action overflow is available from the menu hardware key. The resulting actions popup... is displayed at the bottom of the screen."
You...
Is Ruby pass by reference or by value?
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In traditional terminology, Ruby is strictly pass-by-value. But that's not really what you're asking here.
Ruby doesn't have any concept of a pure, non-reference value, so you certainly can't pass one to a method. Variables are always references to objec...
Eager load polymorphic
... Review and Shop since it allows you to eager load in addition to querying by related fields.
The reason that this is necessary is that ActiveRecord cannot build a join based on reviewable alone, since multiple tables represent the other end of the join, and SQL, as far as I know, does not allow yo...
Hibernate Criteria returns children multiple times with FetchType.EAGER
...n
So actually it should apear multiple times. this is explained very well by the author (Gavin King) himself here:
It both explains why, and how to still get distinct results
Also mentioned in the Hibernate FAQ :
Hibernate does not return distinct results for a query with outer join fetching...
Hibernate: “Field 'id' doesn't have a default value”
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In many cases this problem can also be resolved by just dropping the offending table (or tables), assuming that Hibernate is set up to automatically create/manage the DB schema. To drop tables from a managed schema, SET foreign_key_checks = 0; is your friend. Just be sur...
Preventing Laravel adding multiple records to a pivot table
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You can check the presence of an existing record by writing a very simple condition like this one :
if (! $cart->items->contains($newItem->id)) {
$cart->items()->save($newItem);
}
Or/and you can add unicity condition in your database, it would throw an...