JSONPath Union Operator — Select Multiple Keys or Indices

The Union Operator in JSONPath

The union operator allows you to select multiple properties or array indices in a single expression by listing them inside square brackets, separated by commas.

Syntax

$["key1", "key2", "key3"]       // multiple properties
$.array[0, 2, 4]                // multiple array indices

Selecting Multiple Properties

Given:

{
  "name": "Alice",
  "email": "alice@example.com",
  "phone": "+1-555-0100",
  "address": "123 Main St",
  "age": 30
}

$["name", "email", "phone"] returns ["Alice", "alice@example.com", "+1-555-0100"] — only the three specified fields, ignoring the rest.

Selecting Multiple Array Indices

Given:

{
  "logs": ["INFO: start", "DEBUG: init", "WARN: slow", "ERROR: timeout", "INFO: done"]
}

$.logs[0, 3, 4] returns ["INFO: start", "ERROR: timeout", "INFO: done"] — cherry-picking specific entries by their position.

Combining with Nested Paths

You can use the union operator at any level of a path:

$.users[0, 1].name               // names of the first two users
$.config["db", "cache"].host     // host values from db and cache sections

Union vs. Wildcard vs. Slice

Operator	Syntax	Selection
Union	[0, 2] or ["a", "b"]	Specific items
Wildcard	[*]	All items
Slice	[0:3]	Range of items

The union operator gives you precise control over which elements to include, making it ideal when you know exactly which fields or positions you need.

Implementation Notes

• The result order matches the order you specify in the union, not the document order in all implementations.
• Some implementations require quotes around property names; others accept unquoted identifiers.