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Extracting specific columns from a data frame
...r package, if your data.frame is called df1:
library(dplyr)
df1 %>%
select(A, B, E)
This can also be written without the %>% pipe as:
select(df1, A, B, E)
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Mac SQLite editor [closed]
... info.plist and setting it to YES
Running the app on a device
Open iTunes
Select the device
Select the "Apps" tab
Scroll down to the "File Sharing" section and select the app
The .sqlite file should appear in the right hand pane - select it and "Save to..."
Once it's saved open it up in your favour...
How to get a list of MySQL views?
...to leave the "IN database_name" away if you look for view in the currently selected DB.
– kraftb
Jun 2 '15 at 17:11
To...
Is it possible to select the last n items with nth-child?
Using a standard list, I'm trying to select the last 2 list items. I've various permutations of An+B but nothing seems to select the last 2:
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Generating a UUID in Postgres for Insert statement?
...d to run psql -d dbname -f SHAREDIR/contrib/module.sql and now it works!!! select uuid_generate_v1(); returns 1 now now. Thanks so much!
– anon58192932
Sep 29 '12 at 22:13
5
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SQL Server Profiler - How to filter trace to only display events from one database?
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Under Trace properties > Events Selection tab > select show all columns. Now under column filters, you should see the database name. Enter the database name for the Like section and you should see traces only for that database.
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Eclipse git checkout (aka, revert)
...ing" view, right click the deleted file in the "Unstaged Changes" list and select "Replace with HEAD Revision"
– Vlasta Dolejs
Sep 5 '17 at 8:03
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How to select the last record of a table in SQL?
This is a sample code to select all records from a table. Can someone show me how to select the last record of that table?
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How can I know which radio button is selected via jQuery?
I have two radio buttons and want to post the value of the selected one.
How can I get the value with jQuery?
37 Answers
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SQL “between” not inclusive
... is interpreted as midnight when the day starts.
One way to fix this is:
SELECT *
FROM Cases
WHERE cast(created_at as date) BETWEEN '2013-05-01' AND '2013-05-01'
Another way to fix it is with explicit binary comparisons
SELECT *
FROM Cases
WHERE created_at >= '2013-05-01' AND created_at <...