hi,I know in a columnstore Index, data is compressed and stored in columnar format, segments are built from each column and grouped in a row group. But I have problems figuring out the difference of index storage between usual B-Tree indexes and Columnstore indexes. In B-Tree, there is a nonclustered index built on a key column, the index is looked up in a B-Tree structure, and then on the leaf node, it points to the data in the heap or clustered index by a Row-ID (RID).in a clustered index, there is a pointer on the leaf-level to the entry in the table by a Page-ID (PID) right?My big questions are:-are all standard indexes (clustered/nonclustered) being loaded into memory when needed in a search?-is there still a B-Tree like structure in-memory for the columnstore index, just as usual when searching through the records? just with the difference that more column index values can be in an index page instead of row values, which makes it more effective for column-like queries? -is there a separate index built for every column of the table ( If I include all columns), so for e.g 5 columns, there will be made 5 separate indexes? and if not, where will they store all the other columns in the index pages (because if they store them together,it would be the same as a row storage then I guess?)-I thought the index values are stored in segments, that are stored in BLOB-datatypes, how are they then used for the index? will they all be loaded into the memory when needed?
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