When working with lists in DuckDB, we sometimes need to check whether a list contains specific elements. The list_has_all() function is a handy tool that allows us to verify if all elements of one list exist within another. This function is particularly useful in filtering queries, data validation, and advanced list-based operations.
In this article, we’ll explore how list_has_all() works in DuckDB.
If you’re getting an error that reads something like “Binder Error: Could not find key “…” in struct” when using the array_extract() function in DuckDB, it could be that you’re specifying a non-existent key.
When using DuckDB’s array_extract() function to extract a value from a struct, we must provide a key that actually exists in the struct. Otherwise we’ll end up with an error like the above one.
To fix this issue, be sure to specify a key that actually exists in the struct.
Continue readingDuckDB has a flatten() function that we can use to flatten nested lists. The function concatenates a list of lists into a single list. So whether the outer list contains just one list or multiple lists, we can use the flatten() function to flatten them into one list.
However, it only goes one level deep, so that’s something to keep in mind.
Continue readingDuckDB provides us with a bunch of list concatenation functions that do exactly the same thing; concatenate two lists. Actually, they’re all synonyms and so they can all be used interchangeably. There’s also a more general concatenation function that can also be used on lists.
So this article presents five functions that we can use to concatenate lists.
Continue readingWhen working with DuckDB, sometimes we might need to get the weekday name from a date or timestamp value. And sometimes we might want just the abbreviated weekday name, rather than the full name. For example, we might want Mon instead of Monday.
Continue readingIf you’re getting an error that reads something like “Could not convert string ‘…’ to INT64” when using the generate_subscripts() function in DuckDB, it appears that your second argument is a string, when it should be an integer.
DuckDB’s generate_subscripts() function accepts two arguments; the array as the first argument, and the dimension as the second argument. The second argument must be INT64 (or be able to be implicitly converted to that type). Passing the wrong data type as the second argument can cause the above error to occur.
To fix this issue, make sure that the second argument is compatible with INT64.
In DuckDB, the LEAST() function returns the smallest value from a list of expressions. The function works across various data types and provides flexible comparison capabilities for data analysis tasks.
In this article, we’ll explore DuckDB’s LEAST() function with some simple examples.
DuckDB offers a variety of date functions, one of which is the extract() function. This function is designed to retrieve a specific date part from a date or timestamp value, and it can also be applied to intervals.
In this article, we’ll take a closer look at the extract() function and provide some straightforward examples to illustrate how it works.
In this article we look at how to automatically enclose values in single quotes when outputting DuckDB query results as a list. Using this method, each value is formatted as SQL literals. This can be useful when you want to escape the values for SQL or for some other purpose.
We also look at how CSV output is sometimes quoted with double quotes, and how we can adjust the results by doing things like removing the headers and changing the list separator.
Continue readingIf you’re using DuckDB and you need to check which version you’re running, here are some quick and easy methods to do so.
Continue reading