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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[...
How can I erase all inline styles with javascript and leave only the styles specified in the css sty
...ike only making the code dirtier imho. The best of course would be to only select the elements you need to have the style removed, via ID possibly.
– Jose Faeti
Aug 3 '11 at 13:15
...
How to get the first and last date of the current year?
...
SELECT
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()), 0) AS StartOfYear,
DATEADD(yy, DATEDIFF(yy, 0, GETDATE()) + 1, -1) AS EndOfYear
The above query gives a datetime value for midnight at the beginning of December 31. This ...
Google Play Services Library update and missing symbol @integer/google_play_services_version
...
control click -> properties -> android -> libraries, add -> select the project you just imported -> ok
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Replace a newline in TSQL
...e any of CR, LF or CR+LF. To get them all, you need something like this:
SELECT REPLACE(REPLACE(@str, CHAR(13), ''), CHAR(10), '')
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How to enable MySQL Query Log?
...global general_log = 1;
SET global log_output = 'table';
View the log
select * from mysql.general_log;
Disable Query logging on the database
SET global general_log = 0;
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Best way to check if object exists in Entity Framework?
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hi. how can we check if it exists and after that select all its data?
– virtouso
Apr 7 '15 at 1:27
1
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How to make all Objects in AWS S3 bucket public by default?
...n.s3.amazonaws.com/policygen.html
Fill in the details such as:
In Action select "GetObject"
Select "Add Statement"
Then select "Generate Policy"
Copy the text example:
{
"Id": "Policy1397632521960",
"Statement": [
{
"Sid": "Stmt1397633323327",
"Action": [
"s3:GetObjec...
Cannot drop database because it is currently in use
...ar(50)
SET @DatabaseName = N'YOUR_DABASE_NAME'
DECLARE @SQL varchar(max)
SELECT @SQL = COALESCE(@SQL,'') + 'Kill ' + Convert(varchar, SPId) + ';'
FROM MASTER..SysProcesses
WHERE DBId = DB_ID(@DatabaseName) AND SPId <> @@SPId
--SELECT @SQL
EXEC(@SQL)
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data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...