SAP HANA 2.0 Administration · Table Internals: Stores, Compression, Partitioning & MVCC

Both no-logging and no-logging-retention tables lose data at restart. So what does the RETENTION option actually buy, and what extra risk does the retention variant carry?

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More in Table Internals: Stores, Compression, Partitioning & MVCC

A row-store table has a single-column integer sequence key; another has a composite character key. Which gets plain BTREE and which gets CPBTREE, and why does that make CPBTREE the de-facto default for SAP?

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Memory merge cuts I/O during chunked loads. What asymmetric cost do you accept, and what has to recover the data if that cost is realised?

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