Block bad data, duplicates, and incorrect dates with these custom rules.

One of Excel's simpler lookup functions.

Excel's data validation feature is more versatile than you might think. Learn how to use literal values, input values, list values, and even formulas to restrict input date values using data ...

How to combine values from a column into a single cell using Microsoft Excel’s Power Query Your email has been sent The article How to concatenate values in a single Excel column to a single row shows ...

How do I do that in data.table? Find code for dozens of data tasks in this searchable cheat sheet of R data.table and Tidyverse code. Speed. Concise syntax. Backwards compatibility. But especially ...

See how to join two data sets by one or more common columns using base R’s merge function, dplyr join functions, and the speedy data.table package. R has a number of quick, elegant ways to join data ...

If you see the error “This value doesn’t match the data validation restrictions defined for this cell” when entering a value in an Excel cell, the solutions ...