Engines, internals

Postgres

• Write-Ahead Logging (WAL) mechanism for durability,

• heap pages for table data,

• B-tree or GiST indexes for efficient data retrieval.

  • GiST (Generalized Search tree). GiST indexes are commonly used in PostgreSQL for indexing spatial data (e.g., using the geometry type and associated operators), full-text search (using the tsvector and tsquery types)

Cassandra, HBase

memtable <> SSTable