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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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Create unique constraint with null columns
...es are ugly, too. SQL92 identifiers with spaces in them are a misstep made by a committee. Don't use them.
– wildplasser
Nov 27 '11 at 22:20
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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...
How to persist a property of type List in JPA?
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Will it work with jpa repositories for filtering results by content of that field?
– Please_Dont_Bully_Me_SO_Lords
Mar 1 '19 at 5:41
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Setting background colour of Android layout element
...is somewhat lacking when it comes to some features. I think I picked it up by accident in some external tutorials. Usually it's a good idea to browse the api samples and sample projects though. You can find the code inside the ANDROID_SDK\samples folder (for various android versions). The whole api ...
Yii2 data provider default sorting
... works but the search in index doesn't work now.
– Roby Sottini
Nov 16 '17 at 12:14
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NullPointerException accessing views in onCreate()
... to create an activity-based UI instead of the fragment-based UI preferred by wizard-generated code.
The view is in the fragment layout (fragment_main.xml) and not in the activity layout (activity_main.xml). onCreate() is too early in the lifecycle to find it in the activity view hierarchy, and a ...
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...
Entity Framework Migrations renaming tables and columns
...erated a new Migration in EF 5. As is usual with renames in EF migrations, by default it was going to drop objects and recreate them. That isn't what I wanted so I pretty much had to build the migration file from scratch.
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In SQL, what's the difference between count(column) and count(*)?
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@tsilb: The answer posted by @Alan states "count(*) is computed by looking at the indexes on the table in question rather than the actual data rows" which, if true, invalidates your comment. I appreciate that @Alan may be wrong but I'm interested in t...