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SQL update fields of one table from fields of another one
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I not sure how inheritance will solve this. Do you mean adding an update trigger for A that also updates B? I don't want to synchronize A with B all the time, only upon request. And in such case, I can't use the triggers.
– Nir
May 4 '10...
What does the @ symbol represent in objective-c?
..." doesn't really answer the stated question? The asker says "what does '@' mean in Objective-C?" and the answerer says "It means you're using Objective-C." I think he already knew as much...
– Jon McClung
Aug 23 '18 at 13:44
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Convert UTC/GMT time to local time
...at was.
1. There are probably at least three 'locals' involved. Local may mean Honolulu, or it may mean where your computer is located, or it may mean the location where your customer is located.
2. If you use the built-in functions to do the conversion, it will probably be wrong. This is because ...
What does template mean?
...stackoverflow.com%2fquestions%2f499106%2fwhat-does-template-unsigned-int-n-mean%23new-answer', 'question_page');
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Name
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What is a raw type and why shouldn't we use it?
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What do you mean that, "Java generics are non-reified"?
– Carl G
Dec 15 '12 at 20:07
7
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What's the difference between lapply and do.call?
...example with a list :
X <- list(1:3,4:6,7:9)
With lapply you get the mean of every element in the list like this :
> lapply(X,mean)
[[1]]
[1] 2
[[2]]
[1] 5
[[3]]
[1] 8
do.call gives an error, as mean expects the argument "trim" to be 1.
On the other hand, rbind binds all arguments ro...
Assign multiple columns using := in data.table, by group
...hello
# 4: 1 4 hi hello
# 5: 2 5 hi hello
# 6: 3 6 hi hello
x[ , c("mean", "sum") := list(mean(b), sum(b)), by = a][]
# a b col1 col2 mean sum
# 1: 1 1 hi hello 2.5 5
# 2: 2 2 hi hello 3.5 7
# 3: 3 3 hi hello 4.5 9
# 4: 1 4 hi hello 2.5 5
# 5: 2 5 hi hello 3.5 7
#...
JSON Naming Convention (snake_case, camelCase or PascalCase) [closed]
...row button by Property Name Guidelines->Property Name Format->Choose meaningful property names..
– Panzercrisis
Dec 23 '14 at 14:26
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What do REFRESH and MERGE mean in terms of databases?
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REFRESH means "pull any state changes from the database into my representation". Cascading this is simple; it means that all associated entities are refreshed.
MERGE means something complex that approximates "save" but is more like...
How to find gaps in sequential numbering in mysql?
...going into further details (we'll see them in next paragraphs) this output means that:
No values between 0 and 2
No values between 9 and 22
No values between 24 and 29
No values between 29 and 33
No values between 33 and MAX VALUE
So the basic idea is to do a RIGHT and LEFT joins with the same t...