Hi, @muditbahedia
Thank you for posting in Microsoft Q&A forum.
First, it's recommended to query view instead of table in database, we can query the view v_PackageStatusRootSummarizer to get the source size.
Select SUM(SourceSize) from v_PackageStatusRootSummarizer
Then, I compared the source size in database of mine with the size of SCCMContentLib, they are almost the same size.
But I haven’t figured out their specific differences, I will do more research, if I have further discovery, I will post it here.
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