# Usage

> Indexing with vchordrq and vchordg, MaxSim multi-vector retrieval, quantization types, range queries, and tuning.

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LLMS index: [llms.txt](/llms.txt)

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Section pages:

- [Indexing](/docs/usage/indexing/): VectorChord's index type vchordrq divides vectors into lists and searches only a subset of lists closest to the query vector. It provides fast build time and lo
- [Multi-Vector Retrieval](/docs/usage/multi-vector-retrieval/): Multi-Vector Retrieval is an advanced technique used in Retrieval-Augmented Generation (RAG) systems to enhance document retrieval by leveraging multiple vector
- [Graph Index](/docs/usage/graph-index/): VectorChord's index type vchordg is a disk-based graph index. It has low memory consumption.
- [Quantization Types](/docs/usage/quantization-types/): Quantization can be applied not only to indexes but also directly to vectors. To this end, VectorChord provides data types for quantized vectors.
- [Similarity Filter](/docs/usage/similarity-filter/): Usually, ORDER BY and LIMIT clauses are used to perform vector search. In some cases, you may want to use a WHERE clause to filter out vectors that are far from
- [PostgreSQL Tuning](/docs/usage/postgresql-tuning/): Indexing may be parallelized. Parallelism increases server load and is therefore not enabled by default in PostgreSQL. To enable it, refer to the following SQL.
- [Monitoring](/docs/usage/monitoring/): You can monitor the progress of building a PostgreSQL index by querying the pgstatprogresscreateindex view.
- [Fallback Parameters](/docs/usage/fallback-parameters/): Search parameters are typically configured via GUCs. VectorChord also offers an alternative method, allowing these parameters to be attached directly to an inde
- [Measure Recall](/docs/usage/measure-recall/): In the context of vector search, recall is the ratio of true nearest neighbors to approximate nearest neighbors returned by the index. For example, if the index
- [Prewarm](/docs/usage/prewarm/): After PostgreSQL starts, tables and indexes are loaded from storage into the buffer pool only when they are accessed for the first time. As queries are executed
- [Prefilter](/docs/usage/prefilter/): In a filtered index scan, the index performs the scan first and then PostgreSQL checks whether the filter conditions are satisfied. On this page, "filter" refer
- [Prefetch](/docs/usage/prefetch/): Prefetch dramatically accelerates queries that involve I/O operations. It works by proactively reading buffers into operating system page cache or PostgreSQL's
- [Rerank in Table](/docs/usage/rerank-in-table/): PostgreSQL indexes store row identifiers and the values of the indexed columns. Typically, indexed columns have simple data types, for example, integers or stri
- [Partitioning Tuning](/docs/usage/partitioning-tuning/): For large tables, the partitioning phase dominates both build time and memory consumption.
- [External Build](/docs/usage/external-build/): In addition to using the methods in Partitioning Tuning to achieve shorter build time and lower memory consumption at the cost of QPS and recall, you can also c