JDBC Series
Last updated: June 10, 2026
Mocking is an essential part of unit testing, and the Mockito library makes it easy to write clean and intuitive unit tests for your Java code.
Get started with mocking and improve your application tests using our Mockito guide:
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Get started with understanding multi-threaded applications with our Java Concurrency guide:
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Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:
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Refactor Java code safely — and automatically — with OpenRewrite.
Refactoring big codebases by hand is slow, risky, and easy to put off. That’s where OpenRewrite comes in. The open-source framework for large-scale, automated code transformations helps teams modernize safely and consistently.
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Join the next session, bring your questions, and learn how to automate the kind of work that usually eats your sprint time.
JDBC (Java Database Connectivity) is the foundational API for relational database access in Java, sitting beneath all higher-level abstractions like JPA and Spring Data. Understanding how to connect, query, manage transactions, and handle results at the JDBC level gives us precise control over database interactions and a solid foundation for troubleshooting any data-access layer.
This series covers core JDBC operations from fundamentals to practical patterns, organized by concern: from setting up connections and connection pools, through executing statements and working with result sets, managing schemas and metadata, and diagnosing common errors.
Getting Started with JDBC
- Loading JDBC Drivers
- Jdbc URL Format for Different Databases
- A Comparison Between JPA and JDBC
- A Simple Guide to Connection Pooling in Java
- Best Practices for Sizing the JDBC Connection Pool
Executing Statements
- Batch Processing in JDBC
- A Guide to Auto-Commit in JDBC
- How to Execute Multiple SQL Statements as One in JDBC
- Store File or byte[] as SQL Blob in Java (Store and Load)
- Using “LIKE” Wildcards in Java PreparedStatements
- Inserting Null Into an Integer Column Using JDBC
Working with ResultSets
- Processing JDBC ResultSet With Stream API
- Pagination With JDBC
- Get the Number of Rows in a ResultSet
- Convert ResultSet Into Map
- Converting a JDBC ResultSet to JSON in Java
Connection and Schema Management
- Connecting to a Specific Schema in JDBC
- Extracting Database Metadata Using JDBC
- How to Check if a Database Table Exists with JDBC
- Is java.sql.Connection Thread-Safe?
- Intercept SQL Logging with P6Spy
- Mocking JDBC for Unit Testing
Errors and Troubleshooting
- Fix the Java-MySQL Connection Exception: Public Key Retrieval is not allowed
- Resolving PostgreSQL ERROR: canceling statement due to user request
- Solving “java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver”
- Fix the Exception “Cannot issue data manipulation statements with executeQuery()”
- Tomcat Warning “To Prevent a Memory Leak, the JDBC Driver Has Been Forcibly Unregistered”
