When working with dates in DuckDB, extracting specific components like the day is a common task. DuckDB provides a good range of functions that we can use to help us to perform such a task.
This article presents seven different functions we can use to extract the day from a date in DuckDB.
When working with SQL databases such as DuckDB, dates usually conform to a specific format. In particular, when we create dates in DuckDB, they must conform to the ISO 8601 format (YYYY-MM-DD). It’s the same with time (hh:mm:ss[.zzzzzz][+-TT[:tt]]) and timestamp values (YYYY-MM-DD hh:mm:ss[.zzzzzzzzz][+-TT[:tt]]).
But what if we have a requirement to present these dates or timestamps in a different format?
Fortunately, DuckDB provides us with tools to so. This article explains how to format date and timestamp values according to a specified format.
Sometimes we need to subtract a certain time interval from a date when working with DuckDB. We might want to subtract hours, minutes, days, months, or even years.
Below are two methods we can use to subtract one or more years from a date in DuckDB.
If you’re getting an error that reads “Binder Error: APPROXIMATE QUANTILE can only take parameters in range [0, 1]” in DuckDB, it appears that you’re passing an invalid second argument to the approx_quantile() function.
To fix this issue, make sure the second argument is between 0 and 1.
As an Azure Data Studio user, I was surprised when an alert popped up informing me that Azure Data Studio (ADS) is being retired on February 28, 2026. The message included a link to Microsoft’s recent announcement.
Microsoft now recommends we transition to Visual Studio Code (VS Code) instead.
If you find yourself running a lot of ad-hoc queries that start with SELECT * FROM, you might be interested in this interesting feature of DuckDB.
DuckDB allows us to start queries with the FROM clause. When we do this, DuckDB will return all columns without us needing to specify SELECT *.
One common operation you may find yourself doing occasionally in DuckDB is adding intervals to date and/or time values. DuckDB provides us with a couple of easy ways to do this.
Here are two ways to add days to a date in DuckDB.
If you’re getting an error that reads “Binder Error: RESERVOIR_QUANTILE can only take parameters in the range [0, 1]” in DuckDB, it appears that you’re passing an invalid second argument to the reservoir_quantile() function.
To fix this issue, make sure the second argument is between 0 and 1.
SQLite is a lightweight, serverless SQL database engine commonly used for developing mobile applications, web applications, and embedded systems. Among its various functionalities, SQLite allows developers to create indexes, including unique indexes, to enhance data retrieval speed and enforce constraints on data integrity.
A unique index ensures that all values in a specific column, or combination of columns, are distinct, preventing duplicate entries.
In this guide, we’ll walk through the basics of unique indexes in SQLite, explore when and why to use them, and provide examples of how to create them.
If you’re getting an error that reads something like “Binder Error: Cannot mix values of type …etc” when using the COALESCE() function in DuckDB, it’s probably because you’re using arguments with incompatible types.
To fix this issue, try using CAST() or TRY_CAST() to ensure that all arguments are compatible. Alternatively, make sure the arguments to COALESCE() are of the same type (or at least, compatible types).