weaviate/weaviate · error

target vector is not a string, got %v

Error message

target vector is not a string, got %v

What it means

Each element of the targetVectors array must be a string naming a vector configured on the collection. If an element is not a string (number, null, nested list), ExtractTargets rejects it with this error, printing the offending element.

Source

Thrown at adapters/handlers/graphql/local/common_filters/extract_targets.go:39

	targets, ok := source["targets"]
	if ok {
		targetsGql, ok := targets.(map[string]interface{})
		if !ok {
			return nil, nil, fmt.Errorf("targets is not a map, got %v", targets)
		}
		targetVectorsGQL, ok := targetsGql["targetVectors"]
		if !ok {
			return nil, nil, fmt.Errorf("targetVectors is required field, got %v", targets)
		}
		targetVectorsArray, ok := targetVectorsGQL.([]interface{})
		if !ok {
			return nil, nil, fmt.Errorf("targetVectors is not an array, got %v", targetVectorsGQL)
		}
		targetVectors := make([]string, len(targetVectorsArray))
		for i, value := range targetVectorsArray {
			targetVectors[i], ok = value.(string)
			if !ok {
				return nil, nil, fmt.Errorf("target vector is not a string, got %v", value)
			}
		}

		combinationType, ok := targetsGql["combinationMethod"]
		targetCombinationType := dto.DefaultTargetCombinationType
		if ok {
			targetCombinationType, ok = combinationType.(dto.TargetCombinationType)
			if !ok {
				return nil, nil, fmt.Errorf("combinationMethod is not a TargetCombinationType, got %v", combinationType)
			}
		}

		weightsGQL, ok := targetsGql["weights"]
		var weightsIn map[string]interface{}
		if ok {
			weightsIn = weightsGQL.(map[string]interface{})
		}

View on GitHub (pinned to 75aa4b6d11)

Solutions

1. Ensure every entry is the string name of a configured named vector.
2. Un-wrap over-nested arrays so each element is a plain string.
3. Cross-check names against the collection schema (named vector configuration).

Example fix

// before
targets: { targetVectors: [["title_vector"]] }
// after
targets: { targetVectors: ["title_vector"] }

targets.targetVectors.forEach(v => { if (typeof v !== 'string') throw new Error('targetVectors entries must be strings: ' + JSON.stringify(v)); });

function isNamedVectorList(v) { return Array.isArray(v) && v.length > 0 && v.every(x => typeof x === 'string' && x.length > 0); }

try { ... } catch (e) { if (String(e).includes('target vector is not a string')) { console.error('Fix targetVectors entries to plain strings'); } throw e; }

When it happens

Trigger: targetVectors containing non-string entries, e.g. [1, 2], [null], or [["title_vector"]] from over-nesting in client query variables.

Common situations: Auto-generated query builders that interpolate numeric vector IDs; copy/paste errors nesting the array twice; passing enum values that serialize as numbers.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• targets is not a map, got %v
• targetVectors is not an array, got %v
• weight for target %s is not a float or list of floats, got %
• could not extract objectLimit: %w
• no groupBy must be a list, instead got: %#v

AI-assisted analysis of weaviate/weaviate@75aa4b6d11 (2026-09-04). Data as JSON: /api/errors/c200e8ade7d4a04e. Report an issue: GitHub.