Database Management Systems
Among DuckDB’s many tools for handling list data is the list_grade_up() function. This function works similarly to a sort operation, but instead of returning the sorted values themselves, it returns the indexes that represent the positions of those values in the original list.
Let’s take a quick look.
Continue readingIf you ever find yourself in the situation where you need to count up the number of unique elements in a list in DuckDB, you’ll be happy to know that there’s a list_unique() function that does exactly that.
DuckDB’s list_select() function allows us to extract specific elements from list columns based on their positions. This can be useful when we need to access or manipulate elements within arrays or lists.
If you’re getting an error that reads something like “No function matches the given name and argument types” when using the generate_subscripts() function in DuckDB, it could be that your first argument is not an array. Or it could be that your second argument is not compatible with the INT64 type.
While it’s true that DuckDB has a list_sort() function that allows us to sort lists, it’s also true that there’s a list_reverse_sort() function that sorts lists in reverse order.
Deep amongst DuckDB’s vast selection of list functions lies the list_reverse() function. This function reverses the elements in a list. We simply pass the list to the function and it reverses the order of the elements in that list.
Not to be confused with the list_sort() or list_reverse_sort() functions, the list_reverse() function reverses the order of the items as they currently sit in the list. The ...sort() functions on the other hand, actually perform a sort operation on the list items.
DuckDB has a list_sort() function that does exactly what its name promises; sorts lists.
While the easiest way to use this function is to simply pass a list, we can also pass other arguments to fine-tune the results.
Continue readingDuckDB’s command-line interface (CLI) provides a way to suppress query results using the .mode trash command. This feature is particularly useful in scenarios where you need to execute queries but don’t want their results to be displayed.
Time-based operations are a fundamental aspect of data analysis and manipulation. DuckDB, the in-process analytical database management system, provides robust support for handling time-based operations through its INTERVAL data type.
This article explores the capabilities, syntax, and practical applications of intervals in DuckDB.
Continue readingSQLite provides several ways to determine how many rows are affected by SQL statements such as INSERT, UPDATE or DELETE.
One way of achieving this is with the changes() function. This function returns the number of rows modified by the most recent SQL statement executed in the current session.
Another way is with the .changes dot command.
In this article, we’ll look at an example that uses these options to get the number of rows changed by various SQL statements.
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