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Reverting to a specific commit based on commit id with Git? [duplicate]
...r repo to that state? Or you just want your local repo to look like that?
if you do
git reset --hard c14809fa
It will make your local code and local history be just like it was at that commit. But then if you wanted to push this to someone else who has the new history, it would fail.
if you do...
select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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How to add an integer to each element in a list?
If I have list=[1,2,3] and I want to add 1 to each element to get the output [2,3,4] ,
how would I do that?
11 Answers...
Difference between UIViewContentModeScaleAspectFit and UIViewContentModeScaleToFill?
what is the difference between UIViewContentModeScaleAspectFit and UIViewContentModeScaleToFill ...?
3 Answers
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Random record from MongoDB
...m the mycoll collection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
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Compare DATETIME and DATE ignoring time portion
...e new DATE data type in SQL Server 2008 to compare just the date portion:
IF CAST(DateField1 AS DATE) = CAST(DateField2 AS DATE)
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regex for matching something if it is not preceded by something else
So with regex in java, I want to write a regex that will match if and only if the pattern is not preceded by certain characters. For example:
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What does the fpermissive flag do?
...cs is from errors to warnings. An example is given by the question opener. If you don't know what the edge cases could be, you should not consider using it.
– cli_hlt
Nov 26 '19 at 19:42
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What does !! mean in ruby?
... Why not just return .nil? instead of using !!? Is there a difference?
– ashes999
Sep 3 '14 at 13:52
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Pass a data.frame column name to a function
...ley's Advanced R book is an excellent reference for some of these issues.
If you really want to save the user from typing all those quotes, one option might be to convert bare, unquoted column names to strings using deparse(substitute()):
new_column2 <- function(df,col_name,col1,col2){
col_...