pg-query-parser

The real PostgreSQL query parser

Usage no npm install needed!

<script type="module">
  import pgQueryParser from 'https://cdn.skypack.dev/pg-query-parser';
</script>

README

pg-query-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 pg-query-parser

Example

Rewrite part of a SQL query:

const parser = require('pg-query-parser');

const query = parser.parse('SELECT * FROM test_table').query;

query[0].SelectStmt.fromClause[0].RangeVar.relname = 'another_table';

console.log(parser.deparse(query));

// SELECT * FROM "another_table"

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.

Related