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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...
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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How do I get NuGet to install/update all the packages in the packages.config?
...ve to do is
Right click on the Solution node in Solution Explorer and select
Enable NuGet Package Restore.
Read this article for more details.
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How to create function that returns nothing
...o I make use of this function inside of another function? If I try without SELECT * FROM stamp_user(...), then I get error: query has no destination for result data and if I just write stamp_user(...) then I get syntax error.
– pir
Dec 22 '18 at 18:28
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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(-...
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[...
Where to place the 'assets' folder in Android Studio?
...
Select the app folder and then:
File > New > folder > assets Folder ,
the default location is inside /main folder
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How to read if a checkbox is checked in PHP?
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checkboxes as an array and foreach ($_POST['food'] as $selected_food) to work on checked one is nice, thanks
– bcag2
May 4 at 13:02
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...
With arrays, why is it the case that a[5] == 5[a]?
...D"[2] == *("ABCD" + 2) = *("CD") = 'C'. Dereferencing a string gives you a char, not a substring
– MSalters
Sep 21 '09 at 10:34
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SQL multiple column ordering
... 1478
Thomas | Jefferson | 1826
If you execute the query below:
SELECT * FROM People ORDER BY FirstName DESC, YearOfBirth ASC
The result set will look like this:
FirstName | LastName | YearOfBirth
----------------------------------------
Thomas | More | 1478
Thomas ...