By default, when a query returns a null value in the DuckDB command line interface (CLI), an empty string is displayed. This may or may not be what you want. But if you’re like me, you probably want DuckDB to explicitly tell you that it’s a null value. After all, if an empty string is returned, perhaps the data contained an empty string?
Fortunately, DuckDB provides us with the .nullvalue dot command so that we can change the output of null values.
DuckDB is a fast, efficient, and embeddable SQL database designed for analytical workloads. As with any other RDBMS, a common task is listing all the tables in your DuckDB instance.
This article covers five options for displaying a list of tables in DuckDB.
Continue readingDuckDB is a database management system tailored for analytical tasks. Its command line interface (CLI) provides a convenient way to interact with databases and execute queries. The CLI provides us with the ability to configure the output mode for query results, offering flexibility in how data is displayed or exported.
This article provides a quick overview of how to change the output mode in the DuckDB CLI.
Continue readingDuckDB is a high-performance in-process analytical database management system, often referred to as the “SQLite for analytics.” Its Command Line Interface (CLI) is a useful tool for executing SQL queries, managing databases, and exploring DuckDB’s features.
This article provides a comprehensive guide to the basics of using DuckDB’s CLI, helping beginners and advanced users alike understand how to leverage it effectively.
Continue readingThe .changes dot command in SQLite is a helpful utility for developers working with databases, especially when tracking the number of rows affected by SQL statements like INSERT, UPDATE or DELETE.
When used in the SQLite command-line interface, .changes toggles an option that shows the count of modified rows after executing a command.
This article looks at how the .changes command works, how it can be enabled or disabled, and provides an example to illustrate how it works.
SQLite is a lightweight, self-contained, and highly reliable SQL database engine used widely for developing and testing small-scale applications. One unique feature of SQLite is the set of “dot commands” used in the SQLite command-line interface (CLI) to execute various actions related to database management, navigation, and configuration.
These dot commands are not part of SQL syntax itself but provide a convenient way to manage and interact with SQLite databases.
Continue readingIn Redis, the ZLEXCOUNT command returns the number of elements in a sorted set with a value between two given values. It can be used when we force lexicographical ordering by applying the same score to all members of a sorted set.
Trying to convert a number to a date in SQL Server can be tricky and may not always work. It all depends on the number and what exactly it is that we’re trying to do. That said, here are some scenarios where we can convert a number to a date value.
Continue readingIn Redis, the ZRANGESTORE command works just like the ZRANGE command except that it stores the result in a key.
Basically, it allows us to get all members from a sorted set between a certain range and store them in a new key.
Continue readingIn Redis, the ZMSCORE command allows us to get the score of one or members in a sorted set.