


How Can I Efficiently Stream Large MySQL Result Sets to Avoid Memory Errors?
Dec 02, 2024 am 05:37 AMStreaming Large Result Sets with MySQL
When working with large tables in MySQL, excessive resource consumption and memory errors can arise due to the default behavior of JDBC drivers loading entire result sets into memory. To mitigate this, it's essential to implement proper techniques for streaming data rather than loading it all at once.
Approach
The provided question suggests using statement.setFetchSize(Integer.MIN_VALUE); to limit data loading, but this alone is insufficient. According to the MySQL JDBC driver documentation, setting the result set to TYPE_FORWARD_ONLY and CONCUR_READ_ONLY is necessary for effective streaming:
stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_READ_ONLY); stmt.setFetchSize(Integer.MIN_VALUE);
However, it's crucial to note that this approach has potential drawbacks:
- All rows in the result set must be processed before issuing further queries on the connection.
- Locks are only released once the transaction completes or all results are read or the active result set is closed.
Further Considerations
If setting the result set as TYPE_FORWARD_ONLY and CONCUR_READ_ONLY does not resolve memory issues, the underlying cause may be the storage of data in Java's memory before it's processed. To address this, immediate processing of data as it comes in is required, which might involve significant code modifications. For more information, refer to the provided link in the answer, which addresses a similar issue.
The above is the detailed content of How Can I Efficiently Stream Large MySQL Result Sets to Avoid Memory Errors?. For more information, please follow other related articles on the PHP Chinese website!

Hot Article

Hot tools Tags

Hot Article

Hot Article Tags

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

Reduce the use of MySQL memory in Docker

How do you alter a table in MySQL using the ALTER TABLE statement?

How to solve the problem of mysql cannot open shared library

What is SQLite? Comprehensive overview

Run MySQl in Linux (with/without podman container with phpmyadmin)

Running multiple MySQL versions on MacOS: A step-by-step guide

What are some popular MySQL GUI tools (e.g., MySQL Workbench, phpMyAdmin)?

How do I configure SSL/TLS encryption for MySQL connections?
