Does the reach feature support transactionally safe rollback after a schema change?

Question

Goal: Verify whether the reach feature can safely roll back a schema change after it has been applied, ensuring that the database returns to its prior state without data loss or inconsistency.
Uncertainty: The available research does not contain specific documentation for reach regarding transactional DDL support, savepoints, or versioned snapshots that would guarantee reversible schema modifications. General patterns suggest that safe rollback depends on such mechanisms, but it is unclear if reach implements them, requires explicit configuration, or lacks this capability altogether.
Specific questions: Does reach execute schema‑altering statements within a transaction that can be rolled back? Does it provide versioned snapshots or generate reversible migration scripts? Are there any configuration options or known limitations that affect the safety of rollback after a schema change?

Tasadduq Burney · Answer

Answer
Based on the available information, Reach does not guarantee transactionally safe rollback of schema changes.
Confirmed facts

No public documentation states that Reach executes DDL (CREATE/ALTER/DROP) inside a transaction that can be rolled back.
General behavior of comparable features shows that without explicit versioned snapshots or reversible migration scripts, schema changes are not automatically reversible.
Most underlying databases limit transactional DDL for certain objects, which further reduces the chance of automatic rollback safety.

Likely explanation
Reach most likely forwards schema‑altering statements directly to the target database without wrapping them in a transaction or creating savepoints. Consequently, issuing a ROLLBACK after a Reach‑driven schema change will not revert the database to its prior state; manual intervention or custom migration scripts would be required.
Steps to verify (test environment only)

Consult the official Reach release notes or reference guide for any mention of "transactional DDL", "savepoints", or "snapshot" capabilities.
In a sandbox database, begin a transaction, apply a schema change via Reach (e.g., reach migrate add-column users age INT), then issue ROLLBACK and inspect whether the column persists.
Look for a configuration flag that might enable transactional wrapping, such as reach.transactionalDDL=true or similar, and test its effect if present.

Missing diagnostic detail
If Reach provides a configuration option to wrap DDL statements in a transaction, the answer could change to "yes, when that option is enabled." Please confirm whether such a flag exists in your Reach version.

Does the reach feature support transactionally safe rollback after a schema change?

1 answer

Answer

Confirmed facts

Likely explanation

Steps to verify (test environment only)

Missing diagnostic detail

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