PgSqlParser

PostgreSQL SQL parser for .NET, built on libpg_query, which uses the actual PostgreSQL server source to parse SQL and return the internal PostgreSQL parse tree.

With it you can:

• parse SQL to an AST, and deparse or format it back to SQL
• fingerprint and normalize queries, split scripts and tokenize
• classify statements and find the tables, columns and functions a query uses
• analyse the locks a statement takes and the columns a query returns
• rewrite queries and build parse trees in code
• parse PL/pgSQL

Native libraries are included for Linux (glibc and musl), macOS and Windows on x64 and ARM64, and the package is Native AOT compatible.

Documentation: mysticmind.github.io/pgsqlparser-dotnet

For background on why a query's parse tree is useful, see pg_query 2.0: The easiest way to parse Postgres queries.

Installation

dotnet add package pgsqlparser

Note that the libpg_query libs for all OS'es are already packaged with the assembly.

Platform	Runtime identifiers	Minimum version
Linux (glibc)	linux-x64, linux-arm64	glibc 2.17
Linux (musl, for example Alpine)	linux-musl-x64, linux-musl-arm64	Alpine 3.17
macOS	osx-x64, osx-arm64	macOS 10.15 (Intel), macOS 11.0 (Apple silicon)
Windows	win-x64, win-arm64

This version is built on libpg_query 18.1.0, which uses the PostgreSQL 18.6 parser. It targets .NET 8, .NET 9 and .NET 10, and is compatible with trimming and Native AOT.

The package contains the native library for every platform above. To include only the one you run on, publish with a runtime identifier, for example dotnet publish -r linux-x64. See Keeping deployments small.

Quick start

Every function returns a Result<T> that holds either a Value or an Error, and has an async version.

using PgSqlParser;

// Parse SQL into the PostgreSQL parse tree
var tree = Parser.Parse("SELECT id, name FROM users WHERE id = 42").GetValueOrThrow();
Console.WriteLine(tree.Stmts.Count);   // 1

// Find what a query touches
foreach (var table in tree.GetReferences().Tables)
{
    Console.WriteLine($"{table.Name}: {table.Role}");   // users: Read
}

// Format a query
Console.WriteLine(Parser.Format("select a, b from t where x = 1").GetValueOrThrow());
// SELECT a, b
// FROM t
// WHERE x = 1

// Fingerprint a query: the same query shape always gets the same id
Console.WriteLine(Parser.Fingerprint("SELECT 1").GetValueOrThrow());   // 50fde20626009aba

// Handle a failure without throwing
var result = Parser.Parse("SELECT FROM WHERE");
if (!result.IsSuccess)
{
    Console.WriteLine(result.Error.Message);
}

Documentation

The full guide is at mysticmind.github.io/pgsqlparser-dotnet:

Topic	What it covers
Getting started	Installation, platforms, deployment size and working with Result<T>
Parse trees	Parse, walking, editing, comparing and building trees, typed visitors
Deparse, format and normalize	Deparse, Format, Normalize, NormalizeUtility and Fingerprint
Query analysis	Classify, references, locks, Summary, OperationSummary, ParameterRefs and IsUtilityStmt
Scan, tokenize and split	Scan, Tokenize, SplitWithScanner and SplitWithParser
PL/pgSQL	Parsing function bodies and the SQL inside them
Errors and offsets	Parse errors, cursor positions and non-ASCII text
What's new	Changes in 2.1 and 2.0, and upgrading from 1.x

To work on the documentation, see the docs folder: npm install and npm run dev start it locally.

License

PgSqlParser is licensed under the MIT License.

Copyright (c) 2026, Babu Annamalai babu.annamalai@gmail.com

Refer to libpg_query license for license details on libpg_query.

This project includes code derived from the PostgreSQL project, see LICENSE.POSTGRESQL for details.