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How to take column-slices of dataframe in pandas
...e .loc
See the deprecation in the docs
.loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz, ant, cat, ...
Tracking CPU and Memory usage per process
...tility to save the performance data for your inspection later. To do this, select "Performance Logs and Alerts" in the left-hand panel. (It's right under the System Monitor console which provides us with the above mentioned counters. If it is not there, click "File" > "Add/remove snap-in", click ...
What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
... then the result is the first column of the first row. An example might be SELECT @@IDENTITY AS 'Identity'.
ExecuteReader is used for any result set with multiple rows/columns (e.g., SELECT col1, col2 from sometable).
ExecuteNonQuery is typically used for SQL statements without results (e.g., UPDATE...
How do I clear my local working directory in Git? [duplicate]
...r a tagged empty worktree. My favorite at the moment is to depopulate the root under a set of git worktree subfolders.
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Grouped LIMIT in PostgreSQL: show the first N rows for each group?
...
New solution (PostgreSQL 8.4)
SELECT
*
FROM (
SELECT
ROW_NUMBER() OVER (PARTITION BY section_id ORDER BY name) AS r,
t.*
FROM
xxx t) x
WHERE
x.r <= 2;
sha...
SQL Server Management Studio, how to get execution time down to milliseconds
...able in your proc:
DECLARE @EndTime datetime
DECLARE @StartTime datetime
SELECT @StartTime=GETDATE()
-- Write Your Query
SELECT @EndTime=GETDATE()
--This will return execution time of your query
SELECT DATEDIFF(ms,@StartTime,@EndTime) AS [Duration in millisecs]
AND see this
Measuring Quer...
How to set NODE_ENV to production/development in OS X
...
No one mentioned .env in here yet? Make a .env file in your app root, then require('dotenv').config() and read the values. Easily changed, easily read, cross platform.
https://www.npmjs.com/package/dotenv
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Remove a file from a Git repository without deleting it from the local filesystem
... in next commits
To ignore that folder from next commits make one file in root named .gitignore
and put that folders name into it. You can put as many as you want
.gitignore file will be look like this
/FolderName
share...
How to convert a Hibernate proxy to a real entity object
...ns, as that could potentially load tons of data if you happen to unproxy a root entity.
– Vlad Mihalcea
Nov 28 '19 at 4:15
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F12 no longer works in Visual Studio
...: Resharper > Options > Environment > Keyboard & Menus > (Select Visual Studio under Keyboard Shortcuts) > Apply Scheme > Save
– Rahul R.
Jun 3 '14 at 9:29
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