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Storyboard doesn't contain a view controller with identifier
...using Storyboards.
I was having the same issue, but I could not find the "Identifier" field in the inspector.
Instead, just set the field named "Storyboard ID" to what you would name the Identifier. This field can be found under the "Show the Identity inspector" tab in the inspector.
[Note - comme...
Rails: Adding an index after adding column
...able < ActiveRecord::Migration
def change
add_index :table, :user_id
end
end
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WHERE vs HAVING
...level aliases in GROUP BY, ORDER BY and HAVING.
And are there any downsides instead of doing "WHERE 1" (writing the whole definition instead of a column name)
If your calculated expression does not contain any aggregates, putting it into the WHERE clause will most probably be more efficient.
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Splitting string into multiple rows in Oracle
...i can you please clarify me why the above query gives duplicate rows if i didn't use distinct keyword in query
– Jagadeesh G
Sep 12 '13 at 16:50
2
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How do I use the conditional operator (? :) in Ruby?
...some extra junk after it), but they are not required in the last case as said issue does not arise.
You can use the "long-if" form for readability on multiple lines:
question = if question.size > 20 then
question.slice(0, 20) + "..."
else
question
end
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What's the difference between session.Merge and session.SaveOrUpdate?
...n, do nothing
if another object associated with the session has the same identifier,
throw an exception
if the object has no identifier property, save() it
if the object's identifier has the value assigned to a newly
instantiated object, save() it
if the object is versioned (by a <v...
How to link a Facebook app with an existing fan page
... The key is making sure App Page is the ONLY category. We had "Video Game" and "App Page" and this didn't work until we removed "Video Game." As an aside Facebook's workflow is insane--almost like it was written by a 19-year-old in his dorm room.
– Mike Pandolfini
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JPA: How to have one-to-many relation of the same Entity type
...
Yes, this is possible. This is a special case of the standard bidirectional @ManyToOne/@OneToMany relationship. It is special because the entity on each end of the relationship is the same. The general case is detailed in Section 2.10.2 of the JPA 2.0 spec.
Here's a worked example. F...
PHP + MySQL transactions examples
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The idea I generally use when working with transactions looks like this (semi-pseudo-code):
try {
// First of all, let's begin a transaction
$db->beginTransaction();
// A set of queries; if one fails, an excep...
How to add a primary key to a MySQL table?
...mn, you can always add the primary key:
ALTER TABLE goods ADD PRIMARY KEY(id)
As to why your script wasn't working, you need to specify PRIMARY KEY, not just the word PRIMARY:
alter table goods add column `id` int(10) unsigned primary KEY AUTO_INCREMENT;
...