Hi,
I think that on this link you can find information which you require
https://support.symantec.com/en_US/article.DOC4448.html
In document named SizingSizabilityBestPractices_SEP14.pdf, among others, you can find following:
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For the following client-to-server ratios, Symantec recommends the following databases:
- For installations with a client-to-server ratio of ≤5,000:1, using the default log settings, Symantec recommends the embedded databases
- For installations with a client-to-server ratio >5,000:1, or that require large log sizes, Symantec recommends a separate SQL Server database. For SQL Server database sizing, see the database vendor's sizing tools or guides.
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If you use Embedded database and at one moment you want to migrate it to MS SQL you can follow guidelines from this links (they are little old, but still valid).
https://support.symantec.com/en_US/article.TECH102547.html
https://www.symantec.com/connect/articles/move-database-sepm-embedded-microsoft-sql-server
I hope this helps...
Best regards