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mysql update column with value from another table
...answer if you need to change tableB.value according to tableA.value dynamically you can do for example:
UPDATE tableB
INNER JOIN tableA ON tableB.name = tableA.name
SET tableB.value = IF(tableA.value > 0, tableA.value, tableB.value)
WHERE tableA.name = 'Joe'
...
Pushing app to heroku problem
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For all the people who this does not work, check your ~/.heroku/credentials
If the email or token does not match the account, you won't see your apps.
sh...
Disabling implicit animations in -[CALayer setNeedsDisplayInRect:]
...like you can specify any key you could use in setValue:forKey: method, actually specifying complex key paths like bounds.size.
– pqnet
Apr 8 '12 at 17:41
13
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How do I make a list of data frames?
...to your question, but you want to use = and not <- within the function call. If you use <-, you'll end up creating variables y1 and y2 in whatever environment you're working in:
d1 <- data.frame(y1 <- c(1, 2, 3), y2 <- c(4, 5, 6))
y1
# [1] 1 2 3
y2
# [1] 4 5 6
This won't have the s...
What is the good python3 equivalent for auto tuple unpacking in lambda?
...
No, there is no other way. You covered it all. The way to go would be to raise this issue on the Python ideas mailing list, but be prepared to argue a lot over there to gain some traction.
Actually, just not to say "there is no way out", a third way could be to imp...
List of Rails Model Types
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You can use the following basic field types in model scaffolding, all are supported in ActiveRecord supported databases without any extra gem (MySQL, PostgreSQL, SQLite):
:binary
:boolean
:date
:datetime
:decimal
:float
:integer
:primary_key
:string
:text
:time
:timestamp
In the scaffol...
Check if element exists in jQuery [duplicate]
... are used therefore "#elementId" selects by element. "elementId" would actually select all emenets whose tags are named "elementId"
– Petr Gladkikh
Dec 13 '12 at 7:13
8
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What is wrong with using goto? [duplicate]
...lso read some negative texts about them some years ago):
What is actually wrong with it? Why are goto's even possible in C++ then?
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How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migratio
...r considered a valid date. As documented at the Laravel 5.2 upgrade guide, all timestamp columns should receive a valid default value when you insert records into your database. You may use the useCurrent() column modifier (from Laravel 5.1.25 and above) in your migrations to default the timestamp ...
Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
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Historically, 255 characters has often been the maximum length of a VARCHAR in some DBMSes, and it sometimes still winds up being the effective maximum if you want to use UTF-8 and have the column indexed (because of index length lim...