pgsql-deparser

pgsql-parser

The real PostgreSQL parser for nodejs. The primary objective of this module is to provide symmetric parsing and deparsing of SQL statements. With this module you can modify parts of a SQL query statement and serialize the query tree back into a formatted SQL statement. It uses the real PostgreSQL parser.

The main functionality provided by this module is deparsing, which PostgreSQL does not have internally.

Installation

npm install pgsql-parser

Parser Example

Rewrite part of a SQL query:

const { parse, deparse } = require('pgsql-parser');

const stmts = parse('SELECT * FROM test_table');

stmts[0].RawStmt.stmt.SelectStmt.fromClause[0].RangeVar.relname = 'another_table';

console.log(deparse(stmts));

// SELECT * FROM "another_table"

Deparser Example

The deparser can be used separately, which removes many deps required for the parser:

const { parse } = require('pgsql-parser');
const { deparse } = require('pgsql-deparser');

const stmts = parse('SELECT * FROM test_table');

stmts[0].RawStmt.stmt.SelectStmt.fromClause[0].RangeVar.relname = 'another_table';

console.log(deparse(stmts));

// SELECT * FROM "another_table"

CLI

npm install -g pgsql-parser

usage

pgsql-parser <sqlfile>

Documentation

parser.parse(sql)

Parses the query and returns a parse object.

Parameters

parameter	type	description
query	String	SQL query

Returns an object in the format:

{ query: <query|Object>,
  error: { message: <message|String>,
           fileName: <fileName|String>,
           lineNumber: <line|Number>,
           cursorPosition: <cursor|Number> }

parser.deparse(query)

Deparses the query tree and returns a formatted SQL statement. This function takes as input a query AST in the same format as the query property of on the result of the parse method. This is the primary functionality of this module.

Parameters

parameter	type	description
query	Object	Query tree obtained from parse

Returns a normalized formatted SQL string.

Versions

As of PG 13, PG majors versions maintained will have a matching dedicated major npm version. Only the latest Postgres stable release receives active updates.

Our latest is built with 13-latest branch from libpg_query

PostgreSQL Major Version	libpg_query	Status	npm
13	13-latest	Active development	latest
12	(n/a)	Not supported
11	(n/a)	Not supported
10	10-latest	Not supported	@1.3.1 (tree)

Resources

Related

• libpg-query-node
• libpg_query
• pg_query
• pg_query.go

Credits

• pg-query-parser
• pg-query-native

License: https://github.com/zhm/pg-query-parser/blob/master/LICENSE.md

Thanks to https://github.com/zhm/pg-query-parser we've been able to start this repo and add a lot of functionality