WOS (Write Optimized Store)
Write Optimized Store (WOS) is a memory-resident data structure for short-term data storage. The WOS is typically accessed by data manipulation language (DML) statements that load or remove data:
DELETE. To support very fast data load speeds, WOS stores records without data compression or indexing. A projection in WOS is sorted only when it is queried. It remains sorted as long as no further data is inserted into it. WOS organizes data by epoch and holds both committed and uncommitted transaction data.
For more information, see Use of WOS for Trickle Loads.