---
title: "Functions"
slug: "dev-database-reference-sql-functions"
updated: 2026-11-05T22:32:55Z
published: 2026-11-05T22:32:55Z
canonical: "docs.vastdata.com/dev-database-reference-sql-functions"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vastdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Functions

The functions and operators the VAST Query Engine evaluates, by group. Read Overview first to see why a function on a column runs after the scan, then Operators and predicates; the other pages list each group's functions and what isn't available.

- **[Overview](/develop/docs/dev-database-reference-sql-functions-index)**: How the VAST Query Engine evaluates functions and operators, and why only column-to-constant comparisons are evaluated in VAST DataBase.
- **[All functions A-Z](/develop/docs/dev-database-reference-sql-functions-a-z)**: Every SQL function name the VAST Query Engine knows, with a link to its page, and the names it doesn't have, with what to use instead.
- **[String](/develop/docs/dev-database-reference-sql-functions-string)**: Text functions on VARCHAR values, in four pages. Start with Text basics for length, case, substrings and replacing; Search and split covers finding text and splitting it, Trimming and padding the fixed-width forms, and Regular expressions the regexp functions.
- **[Aggregate and analytic functions](/develop/docs/dev-database-reference-sql-functions-aggregate)**: Every aggregate the VAST Query Engine runs, with types, NULL handling and an example each, how they run and how to make them faster.
- **[JSON functions](/develop/docs/dev-database-reference-sql-functions-json)**: Every JSON function the VAST Query Engine runs on JSON text in VARCHAR columns, with paths, types, NULL handling and how to speed them up.
- **[Date and time functions](/develop/docs/dev-database-reference-sql-functions-date-time)**: Every date, time and interval function the VAST Query Engine runs, what fails without time zones, and how to keep date filters fast.
- **[Numeric and math functions](/develop/docs/dev-database-reference-sql-functions-numeric)**: Every rounding, arithmetic, math, bit and number-formatting function the VAST Query Engine runs, with types, NULLs, errors and an example each.
- **[Conditional and conversion functions](/develop/docs/dev-database-reference-sql-functions-conditional-and-cast)**: CAST, TRY_CAST, CASE, coalesce, nullif, greatest and least in the VAST Query Engine, with types, NULL handling and pushdown.
- **[List functions](/develop/docs/dev-database-reference-sql-functions-lists-and-structs)**: Every list, lambda, struct and map function the VAST Query Engine runs, with types, NULL handling, how they run and how to speed them up.
- **[Map functions](/develop/docs/dev-database-reference-sql-functions-lists-and-structs)**: map_concat, map_from_entries, map, map_entries and 9 more.
- **[Struct functions](/develop/docs/dev-database-reference-sql-functions-lists-and-structs)**: struct_extract_at, struct_extract, struct_pack, row and 2 more.
- **[Utility functions](/develop/docs/dev-database-reference-sql-functions-utility)**: Settings, variables and the search path, logging, PostgreSQL-compatible helpers, sort keys and type names.
- **[Table functions](/develop/docs/dev-database-reference-sql-functions-table-functions)**: Table functions such as range, generate_series and unnest that the VAST Query Engine runs in FROM, and what replaces file readers.
- **[Enum functions](/develop/docs/dev-database-reference-sql-functions-binary-hash-uuid)**: enum_code, enum_first, enum_last, enum_range_boundary and 1 more.
- **[Binary, hash and UUID functions](/develop/docs/dev-database-reference-sql-functions-binary-hash-uuid)**: Bit strings, BLOB data and encodings, hashes, UUIDs and enums in the VAST Query Engine, with types, NULL handling and examples.
- **[Operators](/develop/docs/dev-database-reference-sql-functions-operators-and-predicates)**: Comparison, logical, pattern-matching, arithmetic, bitwise and list operators in the VAST Query Engine, and which predicates VAST DataBase evaluates itself.
- **[Vector distance functions](/develop/docs/dev-database-reference-sql-vector-search)**: array_cosine_distance, array_distance, array_negative_inner_product.