$mustNot

The $mustNot operator excludes documents that match any of the specified conditions. It acts as a filter, removing matching documents from the result set.

The $mustNot operator only filters results—it never adds documents to the result set. This means it must be combined with $must or $should to define which documents to search.

A query with only $mustNot returns no results because there is no base set to filter:

// This returns NO results - nothing to filter
{ $mustNot: { category: "electronics" } }

// This works - $must provides the base set, $mustNot filters it
{ $must: { inStock: true }, $mustNot: { category: "electronics" } }

Excluding Multiple Conditions

When $mustNot contains multiple conditions (via array or object), documents matching ANY of those conditions are excluded. This is effectively an OR within the exclusion:

// Exclude documents that match category="generic" OR price > 500
{ $mustNot: [{ category: "generic" }, { price: { $gt: 500 } }] }

Examples

TypeScript

// Exclude out-of-stock items
await products.query({
  filter: {
    $must: {
      category: "electronics",
    },
    $mustNot: {
      inStock: false,
    },
  },
});

// Exclude multiple conditions
await products.query({
  filter: {
    $must: {
      name: "headphones",
    },
    $mustNot: [{ category: "generic" }, { price: { $gt: 500 } }],
  },
});

Redis CLI

# Exclude out-of-stock items
SEARCH.QUERY products '{"$must": {"category": "electronics"}, "$mustNot": {"inStock": false}}'

# Exclude multiple conditions
SEARCH.QUERY products '{"$must": {"name": "headphones"}, "$mustNot": [{"category": "generic"}, {"price": {"$gt": 500}}]}'