Can DDL Statements Be Rolled Back in Popular SQL Databases?

Rollbackability of data definition language (DDL) statements in SQL databases

In the world of SQL database management, the ability to issue and recall Data Definition Language (DDL) statements is a key consideration. DDL statements such as CREATE TABLE and ALTER TABLE modify the database schema. This raises the question: can these DDL operations be rolled back if necessary?

Transactional DDL for PostgreSQL

PostgreSQL stands out among the major SQL databases with its support for atomic and isolated DDL transactions. According to the PostgreSQL wiki, this allows reliable rollback of DDL statements.

MySQL DDL implicit commit

In contrast, MySQL does not support DDL rollback by default. Issuing a DDL statement in MySQL implicitly commits any pending transactions, making it impossible to revert changes.

Transactional DDL for SQLite

Similar to PostgreSQL, SQLite also seems to support transactional DDL. Rolling back a CREATE TABLE statement in SQLite is possible, although the documentation does not explicitly mention this behavior.

Transactional DDL in other databases

According to reference documentation:

• SQL Server supports transactional DDL.
• Sybase Adaptive Server provides transactional DDL.
• DB2 allows transactional DDL.
• Informix provides transactional DDL.
• Firebird (Interbase) supports transactional DDL.

Oracle Database Description

Oracle database versions prior to 11g Release 2 do not support transactional DDL. However, an alternative mechanism for version-based redefinition is available in newer versions.

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