Query and Indexing in HDF5

Information on the Query and Indexing feature in HDF5 can be found below:

• Description
• Documentation

Description

The Query and Indexing feature introduces APIs and objects for querying HDF5 containers and for creating indexes on the contents of HDF5 containers. A container can be an HDF5 file or another type of object or file that interfaces with the HDF5 library:

• The HDF5 query (H5Q) objects and API routines enable the construction of query requests for execution on HDF5 containers.
• The HDF5 index (H5X) objects and API routines allow the creation of indexes on the contents of HDF5 containers.

These objects and APIs are designed to allow plugins as a means to incorporate third party libraries such as fastbit, to improve performance and versatility.

HDF5 historically has allowed an application developer to select, read and write data, but did not provide a mechanism to select and retrieve pieces without prior knowledge of its contents. The Query and Indexing feature enables users to issue a query by use of a previously generated index (so that the data does not have to be accessed) and quickly obtain the elements that match the specific query.

Documentation

The following documentation is available for the Query and Indexing feature:

• HDF5 Query and Indexing User Guide (PDF)
• Query and Indexing in HDF5 RFC