“Exploring DUCKDB: The Fast, Embeddable Analytical Database for Modern Data Challenges”

Martin Jurado Pedroza
6 min readAug 11, 2023

Nowadays, you are aware that a large number of tools are available for managing information, and that new ones frequently develop depending on the sort of information you need to manage or store. This makes it challenging to choose the best tool.

In this article, we will discuss DUCKDB, an analytics tool that benefits businesses and their data teams.

DuckDB is an in-memory analytical database management system designed for high-performance querying and analytics on large datasets. It is built with a focus on providing fast query execution times and efficient use of modern hardware, including CPUs and GPUs. DuckDB aims to bridge the gap between traditional row-oriented databases and analytical columnar databases by offering a balance between the two paradigms. Here are some key features and benefits of DuckDB:

  1. In-Memory Processing: DuckDB operates entirely in-memory, which means data is stored in RAM for rapid access. This approach allows for extremely fast query processing speeds compared to traditional disk-based databases.
  2. Columnar Storage: DuckDB stores data in a columnar format, which is highly efficient for analytical workloads. Columnar storage minimizes I/O operations by reading only the columns needed for a particular query, reducing the overall data transferred and improving performance.
  3. Vectorized Query Processing: DuckDB employs vectorized query execution, which performs operations on entire vectors of data at once rather than individual rows. This technique takes advantage of modern CPU architectures and SIMD (Single Instruction, Multiple Data) instructions for optimized processing.
  4. GPU Acceleration: DuckDB supports GPU acceleration for certain query operations. This means that complex analytical queries can be offloaded to the GPU, resulting in even faster execution times for compatible hardware.
  5. Open Source: DuckDB is an open-source project, making it accessible to the broader developer community. This openness encourages collaboration and allows for customization to fit specific use cases.
  6. Low Latency: Due to its design principles and optimizations, DuckDB can provide low-latency query responses, making it suitable for interactive and ad-hoc analytics.
  7. No Indexing Overhead: Unlike many traditional databases, DuckDB does not rely heavily on indexing for performance. Instead, it uses techniques like bitmap indexes and early-out query processing to minimize indexing overhead.
  8. SQL Compatibility: DuckDB supports a wide range of SQL operations, making it familiar to developers and analysts who are accustomed to working with SQL.
  9. Small Footprint: DuckDB’s compact size and efficient memory utilization make it suitable for resource-constrained environments, including embedded systems and edge devices.
  10. Ease of Use: DuckDB is designed to be easy to set up and use. Its focus on SQL compatibility and its integration with common programming languages simplify the development and deployment of analytical applications.

DuckDB can play a significant role in various fields within the broader domain of data science, data engineering, and big data analytics. Here’s how DuckDB can be involved in these fields:

  1. Data Science:
  • Exploratory Data Analysis (EDA): Data scientists often need to perform quick exploratory analysis on large datasets. DuckDB’s in-memory processing and vectorized query execution can facilitate rapid data exploration and visualization.
  • Feature Engineering: Feature engineering involves creating new features from existing data. DuckDB’s efficient query execution can speed up the process of generating and testing new features.
  • Model Training: Data scientists can leverage DuckDB to preprocess and transform data before training machine learning models. Its columnar storage can be especially beneficial for selecting and transforming features efficiently.
  • Model Evaluation: Analyzing the performance of trained models on large datasets requires efficient querying. DuckDB’s query performance can help in evaluating model accuracy and effectiveness.

2. Data Engineering:

  • Data Transformation: In the data engineering phase, DuckDB can be used to transform and clean raw data before loading it into a data warehouse or other storage systems.
  • Batch Processing: DuckDB can be used for batch processing tasks, such as aggregating, filtering, and joining large datasets, which are common in ETL (Extract, Transform, Load) processes.
  • Data Integration: When integrating data from multiple sources, DuckDB’s query capabilities can assist in data merging and alignment.

3. Big Data Analytics:

  • Efficient Analytics: DuckDB’s design for efficient analytical queries makes it a suitable choice for big data analytics. It can help process large volumes of data quickly and provide insights for decision-making.
  • Interactive Querying: Big data analytics often involve interactive querying for real-time insights. DuckDB’s low-latency query processing can support these requirements.
  • Parallelism and Concurrency: DuckDB’s support for multi-threading and GPU acceleration allows it to process queries in parallel, enhancing performance on large datasets.

Some examples Python and Scala:

Python:

import duckdb

# Connect to the database
con = duckdb.connect(database=':memory:')

# Create a table and load data
con.execute("CREATE TABLE sales (product TEXT, amount INTEGER)")
con.execute("INSERT INTO sales VALUES ('Product A', 100), ('Product B', 200), ('Product C', 150)")

# Perform a query and display results
result = con.execute("SELECT * FROM sales WHERE amount > 150")
print(result.fetchall())

# Close the connection
con.close()

Scala:

import org.duckdb.DuckDB

// Create an instance of the database
val db = new DuckDB()

// Connect to the database
val con = db.connect()

// Create a table and load data
con.execute("CREATE TABLE sales (product TEXT, amount INTEGER)")
con.execute("INSERT INTO sales VALUES ('Product A', 100), ('Product B', 200), ('Product C', 150)")

// Perform a query and display results
val result = con.execute("SELECT * FROM sales WHERE amount > 150")
while (result.next()) {
println(result.getString(0) + " | " + result.getInt(1))
}

// Close the connection and the database instance
con.close()
db.close()

The line con = duckdb.connect(database=':memory:') is creating a connection to a DUCKDB database, where the data is stored in memory rather than in a file on disk.

In DUCKDB, the ':memory:' string as the database name indicates that you want to create an in-memory database. This type of database is temporary and exists only for the duration of the program's execution. It's often used for quick data exploration, testing, or scenarios where you don't want to save the data permanently.

In the provided code examples, con is a connection object that you use to interact with the DUCKDB database. You can use this connection to execute SQL queries, insert data, update records, and more. Once you're done with your operations, you can close the connection to release the resources.

Here’s what the code does step by step:

  1. import duckdb: This imports the DUCKDB library for Python or Scala.
  2. con = duckdb.connect(database=':memory:'): This line creates a connection object named con to an in-memory DUCKDB database.
  3. You can then use the con connection object to execute SQL queries and other database operations as needed.

Remember that in-memory databases are particularly useful for temporary data manipulation. Data stored in an in-memory database is lost when the program ends or the connection is closed, as there’s no persistent storage involved.

Conclusion:

DuckDB’s benefits over other databases stem from its unique combination of columnar storage, vectorized query processing, and in-memory operations. It aims to provide efficient data processing without the need for extensive indexing and with minimal overhead. This makes it particularly suitable for analytical workloads where fast query performance and low latency are essential, such as data exploration, reporting, and business intelligence.

In all these fields, DuckDB’s features such as in-memory processing, columnar storage, vectorized query execution, and GPU acceleration can contribute to improved query performance and reduced processing time. This can lead to faster insights, more efficient workflows, and the ability to handle larger datasets effectively.

While DuckDB is not a replacement for all aspects of data processing (such as transactional systems), it excels in analytical scenarios where the focus is on querying and aggregating data. Its open-source nature and compatibility with SQL also make it accessible to a wide range of data professionals, from data scientists and analysts to data engineers and developers.

Reference:

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Martin Jurado Pedroza

My name is Martin Jurado, and I am a technology enthusiast with experience in data, innovation, development, and design. 🤓