Analyze Index

Table of Contents



ANALYZE INDEX scans an index and reports its statistics as a message. Use it to judge whether an index is selective enough to be useful.
  • Schema, Name, Id, Unique, Created, Modified and the indexed fields (Attributes).
  • Distinct Keys: the number of distinct values.
  • Total Doc Refs: the number of indexed documents.
  • Single-Doc Keys: the number of values that identify exactly one document.
  • Min / Max / Avg Docs/Key: how many documents share a value.
  • Key Data and Value Data: the size of the index.
  • Selectivity: distinct values divided by documents. 100% means every value identifies one document; low values mean the index narrows a search down very little.


round-pushpin Analyzes the IX_Word_Text index.
ANALYZE INDEX IX_Word_Text ON WordList:Word




Home
The home page
SQL :: Alter Index
Creates and drops indexes and unique keys.
SQL :: Alter Schema
Creates, alters and drops schemas.
SQL :: Analyze Schema
Reports the size of a schema's documents and the statistics of its indexes.
SQL :: Attach Schema
Copies a detached schema (namespace) into the database.
SQL :: Create Index
Creates an index or a unique key to speed up queries.
SQL :: Keywords
A breakdown of all of the statements and keywords supported by the query processor.
SQL :: Rebuild Index
Rebuilds an index from the documents in its schema.