As mentioned previously, each memory-optimized table must have at least one index because it is the indexes that connect the rows together (more on this later). The indexes on memory-optimized tables must be created as a part of the
CREATE TABLE statement. You can’t use the
CREATE INDEX statement to create an index for a memory-optimized table after the table has already been created. Memory-optimized tables support a maximum of eight indexes, including the primary key index, and unique indexes are not allowed except for the primary key index.
Indexes on memory-optimized tables are never written to disk, not even to the transaction log. Only the data rows, and changes to the data, are written to the transaction ...