https://www.youngju.dev/blog 천천히 올바르게. AI Researcher & DevOps Engineer Youngju's tech blog. GPU/CUDA, LLM, MLOps, Kubernetes AI workloads, distributed training, and data engineering. ko fjvbn2003@gmail.com (Youngju Kim) fjvbn2003@gmail.com (Youngju Kim) Tue, 16 Jun 2026 00:00:00 GMT https://www.youngju.dev/blog/database/2026-06-16-large-table-online-ddl-migration.en https://www.youngju.dev/blog/database/2026-06-16-large-table-online-ddl-migration.en Run an ALTER against a table with hundreds of millions of rows and your service can grind to a halt. This post walks through the limits of MySQL native Online DDL, how trigger-based pt-online-schema-change and binlog-based gh-ost actually work, PostgreSQL CREATE INDEX CONCURRENTLY and lock_timeout, chunked backfills, throttling, cut-over, and rollback from an operational point of view. Tue, 16 Jun 2026 00:00:00 GMT fjvbn2003@gmail.com (Youngju Kim) databasemysqlpostgresqlmigrationgh-ostonline-ddldevops https://www.youngju.dev/blog/database/2026-06-16-large-table-online-ddl-migration.ja https://www.youngju.dev/blog/database/2026-06-16-large-table-online-ddl-migration.ja 数億行のテーブルに ALTER を打った瞬間、サービスが止まることがあります。MySQL ネイティブ Online DDL の限界から、トリガーベースの pt-online-schema-change とバイナリログベースの gh-ost の動作原理、PostgreSQL の CREATE INDEX CONCURRENTLY と lock_timeout、チャンクバックフィル、スロットリング、カットオーバー、ロールバックまでを運用視点で整理します。 Tue, 16 Jun 2026 00:00:00 GMT fjvbn2003@gmail.com (Youngju Kim) databasemysqlpostgresqlmigrationgh-ostonline-ddldevops https://www.youngju.dev/blog/database/2026-06-16-large-table-online-ddl-migration https://www.youngju.dev/blog/database/2026-06-16-large-table-online-ddl-migration 수억 행 테이블에 ALTER를 거는 순간 서비스가 멈출 수 있습니다. MySQL 네이티브 Online DDL의 한계부터 트리거 기반 pt-online-schema-change와 바이너리 로그 기반 gh-ost의 동작 원리, PostgreSQL의 CREATE INDEX CONCURRENTLY와 lock_timeout, 청크 백필과 스로틀링, 컷오버와 롤백까지 실전 관점으로 정리합니다. Tue, 16 Jun 2026 00:00:00 GMT fjvbn2003@gmail.com (Youngju Kim) databasemysqlpostgresqlmigrationgh-ostonline-ddldevops