fix: invalid cast exception

[ProgrammingByPermutation]

Fixing invalid cast exception raised when performing database migrations

[mysql-oca-bot]

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[kollabara]

Hey, is there any updates for this PR?

It should fix an issue with async migration

[ProgrammingByPermutation]

Hey, is there any updates for this PR?

It should fix an issue with async migration

My fault! I was going through the OCA process and I didn't notice the emails for additional information were going to my spam folder. Working with Lenka Kasparova now to get the OCA approved.

[mysql-oca-bot]

Hi, thank you for your contribution. Please confirm this code is submitted under the terms of the OCA (Oracle's Contribution Agreement) you have previously signed by cutting and pasting the following text as a comment:
"I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it."
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[ProgrammingByPermutation]

I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.

[omachavez]

This PR is part of the fix for bug 116704

[mysql-oca-bot]

Hi, thank you for your contribution. Your code has been assigned to an internal queue. Please follow
bug http://bugs.mysql.com/bug.php?id=118282 for updates.
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