Hash access paths (deprecated)
Db2 can use hash access paths to directly access a single row in a table and avoid scanning the table or index. Hash-organized table spaces are deprecated and will be unsupported in the future.
Hash-organized tables are deprecated, and applications that run at APPLCOMPAT levelV12R1M504 or higher cannot create hash-organized tables or alter existing tables to use hash-organization. Existing hash-organized tables remain supported, but they will be unsupported in the future.
Db2 can generate a hash access path from the equal predicate of an SQL statement that fetches only a single row of a table. This access method is faster and more efficient than scanning the table or the index.
Hash access can reduce the query access time and the CPU load for queries that require access to a single row. However, tables that are enabled for hash access might require as much as twice the amount of disk space as tables that are not organized for hash access.