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How can I make a JPA OneToOne relation lazy
...ly slow. I profiled the view and noticed that there was one query executed by hibernate which took 10 seconds even if there only were two object in the database to fetch. All OneToMany and ManyToMany relations were lazy so that wasn't the problem. When inspecting the actual SQL being executed, I...
Use JSTL forEach loop's varStatus as an ID
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The variable set by varStatus is a LoopTagStatus object, not an int. Use:
<div id="divIDNo${theCount.index}">
To clarify:
${theCount.index} starts counting at 0 unless you've set the begin attribute
${theCount.count} starts countin...
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...
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...
SQL WHERE.. IN clause multiple columns
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@sleske: EXISTS is by far better: see my comments in my answer. And test it first,. @mrdenny: I misread your answer at first, I'd use EXISTS too
– gbn
Jul 16 '09 at 8:17
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WHERE vs HAVING
...ber") after HAVING and not WHERE in MySQL?
WHERE is applied before GROUP BY, HAVING is applied after (and can filter on aggregates).
In general, you can reference aliases in neither of these clauses, but MySQL allows referencing SELECT level aliases in GROUP BY, ORDER BY and HAVING.
And are t...
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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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 ...
MySql Table Insert if not exist otherwise update
... It might be needed to create UNIQUE constraint for Timestamp by using ALTER TABLE AggregatedData ADD UNIQUE (Timestamp)
– Avyakt
Jan 19 '15 at 19:13
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