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Select all elements with “data-” attribute without using jQuery
Using only JavaScript, what is the most efficient way to select all DOM elements that have a certain data- attribute (let's say data-foo ). The elements may be different tag elements.
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Switching between GCC and Clang/LLVM using CMake
...sudo update-alternatives --config c++
Will print something like this:
Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/bin/g++ 20 auto mode
1 /usr/bin/clang++ 10 manual mode
2 ...
Use email address as primary key?
... key. Email address may be a bit much, but a CASCADE UPDATE for a PK of 2-character country code isn't a big deal.
– Matthew Wood
Sep 27 '10 at 20:58
5
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What is the difference between a “function” and a “procedure”?
... a Procedure, whereas in a Function we can't.
In SQL:
A Procedure allows SELECT as well as DML (INSERT, UPDATE, DELETE) statements in it, whereas Function allows only SELECT statement in it.
Procedures can not be utilized in a SELECT statement, whereas Functions can be embedded in a SELECT stateme...
MySQL convert date string to Unix timestamp
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Here's an example of how to convert DATETIME to UNIX timestamp:
SELECT UNIX_TIMESTAMP(STR_TO_DATE('Apr 15 2012 12:00AM', '%M %d %Y %h:%i%p'))
Here's an example of how to change date format:
SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(STR_TO_DATE('Apr 15 2012 12:00AM', '%M %d %Y %h:%i%p')),'%m-%d-...
Difference between `const shared_ptr` and `shared_ptr`?
...);
sA->a = 4; // compile-error
return sA;
}
int main(int argc, char** argv) {
f1();
f2();
return 0;
}
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Repeat each row of data.frame the number of times specified in a column
...es
library(dplyr)
df %>%
slice(rep(seq_len(n()), freq)) %>%
select(-freq)
# var1 var2
#1 a d
#2 b e
#3 b e
#4 c f
#5 c f
#6 c f
seq_len(n()) part can be replaced with any of the following.
df %>% slice(rep(1:nrow(df), freq)) %>% select(-...
Pass Array Parameter in SqlCommand
...AddWithValue(parameters[i], items[i]);
}
cmd.CommandText = string.Format("SELECT * from TableA WHERE Age IN ({0})", string.Join(", ", parameters));
cmd.Connection = new SqlConnection(connStr);
UPDATE: Here is an extended and reusable solution that uses Adam's answer along with his suggested edit....
How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...
What is the difference between onBlur and onChange attribute in HTML?
...
An example to make things concrete. If you have a selection thus:
<select onchange="" onblur="">
<option>....
</select>
the onblur() is called when you navigate away. The onchange() is called when you select a different option from the selection - i.e....