Enhancements to In-Memory OLTP in SQL 2016

In-Memory OLTP:

It is introduced in SQL Server 2014 and they enhanced many things in 2016 release.

Find below the list of enhancements that have been made in SQL Server 2016:

Feature/Limit	SQL Server 2014	SQL Server 2014
Maximum size of table	256 GB	2 TB
LOB (varbinary(max), [n]varchar(max))	Not Supported	Supported
Transparent Data Encryption (TDE)	Not Supported	Supported
ALTER PROCEDURE / sp_recompile	Not Supported	Supported
Nested natively compiled procedure	Not Supported	Supported
Natively-compiled scalar UDFs	Not Supported	Supported
ALTER TABLE	Not Supported	Supported (Only Offline)
Indexes on NULLable columns	Not Supported	Supported
Foreign Keys	Not Supported	Supported
Check/Unique Constraints	Not Supported	Supported
Parallelism	Not Supported	Supported
OUTER JOIN, OR, NOT, UNION, DISTINCT, EXISTS, IN	Not Supported	Supported

ALTER TABLE is an offline operation, by using this we can do following things:

a. Adding columns

b. Dropping columns

c. Indexes

d. Constraints

We can also change the bucket count values with REBUILD option but it needs 2x memory.