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Day: July 7, 2023

File Renaming in R

Steven Sanderson renames a file:

Managing files is an essential task for any programmer, and when working with R, the file.rename() function can become your best friend. In this blog post, we’ll explore the ins and outs of file.rename(), discuss its syntax, provide real-life examples, and share some best practices to empower you in your file management endeavors. So grab a cup of coffee and let’s dive into the world of file.rename()!

Click through for two examples. But do read the documentation if you’re running on Windows and dealing with symbolic links.

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Customizing a Shiny App Theme

Peter Baranovskiy doesn’t want bog standard but is okay with mostly standard:

There are multiple ways to style or theme a Shiny app. A high-level overview is available in the Mastering Shiny book by Hadley Wickham. Here I’ll show the easiest way to do this. If you need to build an entirely – or mostly – new Shiny theme (e.g. a corporate theme), this post is probably not for you. In that case bslib may be the best starting point. Otherwise, if you are generally happy with a pre-made theme and just want to tweak some of its elements, read on.

This post is based on an actual app, so that you can see how it all works. Here’s the app’s source.

Click through to see what kinds of changes you can make without a major overhaul.

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Parameterizing Jupyter Notebooks

John Mount shows off a feature:

I’d like to share a great new feature in the wvpy package (available at PyPi).

This package is useful in converting Jupiter notebooks to/from python, and also in rendering many parameterized notebooks. The idea is to make Jupyter notebook easier to use in production.

The latest feature is an extension of notebook parameterization. In addition to the init_code and output_suffix features, which allow adding arbitrary code to notebooks and saving multiple renders of the same notebook under different (non-coliding!) names. The new sheet_vars feature allows the insertion of arbitrary data into notebook renders (in addition to the earlier code insertion facility).

Click through for an example on how to use this. Several years ago, I would have considered this to be outstanding. Today, I think it’s cool, but I’ve also gravitated toward using notebooks as an intermediary step rather than a final product, so it’s less critical for me these days.

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Performance Optimizing Cosmos DB

Harshvardhan Singh has a few tips for us:

As with the other databases, indexing is the first go-to option to improve query performance. The same is the case with Cosmos DB as well. Below are a few points which you can leverage to optimize the indexing strategy for Cosmos DB. 

Indexes are kind of similar to indexing in SQL Server in intent, though different enough in implementation that you’ll want to read up on them. Harshvardhan also includes some tips around data modeling and querying data.

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Impact of and Limitations to Parameter Tuning in Postgres

Henrietta Dombrovskaya wraps up a series on PostgreSQL parameters:

In this first blog, we didn’t provide any examples of the practical impact of parameters tuning on performance. Indeed, it is challenging to model such an impact on the training database. 

In this blog, we will segue from discussing PostgreSQL system parameters best practices to other ways of performance tuning. Moreover, we will demonstrate that essential database performance tuning goes beyond choosing the appropriate parameters settings.

Click through for that post.

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Azure DataSync: Cannot Insert NULL Value

Jose Manuel Jurado Diaz does some sleuthing:

In this blog article, we will delve into a common error encountered when synchronizing data with Azure SQL DataSync. We’ll explore the error message “Error #1: SqlException Error Code: -2146232060 – SqlError Number: 515, Message: Cannot insert the value NULL into column ‘ID’, table ‘dbo.Customers’; column does not allow nulls. INSERT fails. SqlError Number: 3621, Message: The statement has been terminated.” We will provide a detailed explanation of the error and its possible causes, followed by a T-SQL code snippet that reproduces the error scenario.

Click through for four possible causes.

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