feat(ENG-758673): add DbRestoreOverwritePolicy to Restore-CohesityMSSQLObject

[deepayan-bose-cohesity]

Summary

Adds a -DbRestoreOverwritePolicy switch parameter to Restore-CohesityMSSQLObject, bringing it to parity with Restore-CohesityRemoteMSSQLObject.

The cmdlet now always sets sqlRestoreParameters.overwritePolicy on the POST /public/restore/applicationsRecover request:

Switch state	overwritePolicy sent
-DbRestoreOverwritePolicy specified	kOverwrite
Switch omitted (default)	kFailIfExists

Background

Restore-CohesityRemoteMSSQLObject already exposes -DbRestoreOverwritePolicy for inactive-job restores via the legacy Iris API. The local Restore-CohesityMSSQLObject cmdlet (C# implementation using the public restore API) had no equivalent option, so users could not request overwrite behavior when restoring SQL objects through the standard cmdlet.

The SqlRestoreParameters model already includes an overwritePolicy field with kOverwrite and kFailIfExists enum values — no model or API contract changes were required.

Changes

• RestoreCohesityMSSQLObject.cs
  • Added optional -DbRestoreOverwritePolicy switch parameter with cmdlet help text
  • Always sets SqlRestoreParameters.OverwritePolicy before submitting the restore task:
    • KOverwrite when the switch is present
    • KFailIfExists when the switch is omitted (explicit default, documented in help text)

Backward compatibility

Restore semantics are unchanged: without the switch, restore continues to fail if the database already exists at the target. The amendment makes this explicit in the request payload by always sending overwritePolicy (kFailIfExists by default) rather than omitting the field.

Test plan

• Restore a SQL database to a target where the database already exists without -DbRestoreOverwritePolicy — verify fail-if-exists behavior; confirm request payload contains "overwritePolicy": "kFailIfExists"
• Restore the same scenario with -DbRestoreOverwritePolicy — verify restore succeeds and overwrites the existing database; confirm payload contains "overwritePolicy": "kOverwrite"
• Compare request payload with Restore-CohesityRemoteMSSQLObject -DbRestoreOverwritePolicy to confirm both set overwritePolicy: kOverwrite when overwrite is requested
• Run Get-Help Restore-CohesityMSSQLObject -Parameter DbRestoreOverwritePolicy to verify help text documents the kFailIfExists default

Related

• Jira: https://jira.cohesity.com/browse/ENG-758673
• Epic: https://jira.cohesity.com/browse/ENG-758617
• RFPE: https://jira.cohesity.com/browse/RFPE-2273

[deepayan-bose-cohesity]

Amendment (post-review update)

The implementation was refined after initial review:

Before: overwritePolicy was only set when -DbRestoreOverwritePolicy was specified; the field was omitted from the request otherwise.

After: overwritePolicy is always set on every restore request:

applicationRestoreObject.SqlRestoreParameters.OverwritePolicy = DbRestoreOverwritePolicy.IsPresent
    ? Model.SqlRestoreParameters.OverwritePolicyEnum.KOverwrite
    : Model.SqlRestoreParameters.OverwritePolicyEnum.KFailIfExists;

• Switch present → "overwritePolicy": "kOverwrite"
• Switch omitted → "overwritePolicy": "kFailIfExists" (explicit default)

Cmdlet help text was also updated to document that the default is kFailIfExists when the switch is not specified.

Behavior impact: Restore semantics are unchanged — fail-if-exists without the switch, overwrite with it. The difference is that the default policy is now explicitly sent in the JSON payload rather than relying on Iris server-side defaults.