累积更新是否包含Service Pack？

Question

I wonder if SQL Server CUs contain lower Service Packs. I am asking this because I have a SQL Server 2014 which was patched automatically with CU7 and later that week someone applied Service Pack 2 and a bug that was fixed started appearing again, this bug was fixed on CU3 BTW. For what I saw SP2 was released before CU3 and CU7 but since it was installed later seems that it overwrote the bug fix, even though the SQL Server build number was 12.2.5556.0, it did not contain the fix.

In the end I installed latest CU (CU8) and it was fixed again, but I wonder why it did not detect that CU was ahead of the SP?

Here is the sequence of installation:

It was confirmed on the Windows Update History:

Answer 1

CU's are relevant to a base service pack (eg SP1 CU1 is a completely different build to SP2 CU1, and contain completely different fixes). They don't include service packs but do contain all previous CU's for their base service pack.

Service packs & their CU's may or may not contain fixes found in CU's for an earlier SP.

As far as I can tell, what happened here is you've gone from SP1 (or RTM) CU7 (builds 12.0.4468.0 / 12.0.2495.0) to SP2 CU8 (build 12.0.5557.0)

The link below can be used to check builds & what fixes are in which SP/CU. Clicking through to the bug itself will also tell you which SP/CU's its fixed in.

https://support.microsoft.com/en-gb/help/2936603/sql-server-2014-build-versions