Search Indexes

Search Parameter Index are used to index resources for searching.

The table starts with HFJ_SPIDX (Search Parameter Index) used to index resources for searching. When a resource is created or updated, a set of rows will be added in the tables. These are used for finding appropriate rows to return when performing FHIR searches. There are dedicated tables for supporting each of the non-reference FHIR Search Datatypes: Date, Number, Quantity, String, Token, and URI:

• HFJ_SPIDX_DATE
• HFJ_SPIDX_NUMBER
• HFJ_SPIDX_QUANTITY
• HFJ_SPIDX_QUANTITY_NRML
• HFJ_SPIDX_STRING
• HFJ_SPIDX_TOKEN
• HFJ_SPIDX_URI

Note:

Reference search parameters are implemented using the HFJ_RES_LINK table above.

The SPIDX tables leverage "hash columns", which contain a hash of multiple columns in order to reduce index size and improve search performance. Hashes currently use the MurmurHash3_x64_128 hash algorithm, keeping only the first 64 bits in order to produce a LongInt value. For example, all search index tables have columns for storing the search parameter name (SP_NAME) and resource type (RES_TYPE). An additional column which hashes these two values is provided:

HASH_IDENTITY