What causes "No value found" in dgraph-io/dgraph?

Validate all variable values are non-empty strings before calling the parse/mutation API with the variables map

No value found

Error message

No value found

What it means

parseValue converts a query variable (varInfo with Type and Value) into a typed types.Val. If the variable's Value string is empty there is nothing to parse, so the library returns 'No value found' immediately, before any type-specific parsing.

Source

Thrown at dql/parser.go:312

	vm = make(map[string]varInfo)
	for k, v := range variables {
		vm[k] = varInfo{
			Value: v,
		}
	}
	return vm
}

// Request stores the query text and the variable mapping.
type Request struct {
	Str       string
	Variables map[string]string
}

func parseValue(v varInfo) (types.Val, error) {
	typ := v.Type
	if v.Value == "" {
		return types.Val{}, errors.Errorf("No value found")
	}

	switch typ {
	case "int":
		{
			if i, err := strconv.ParseInt(v.Value, 0, 64); err != nil {
				return types.Val{}, errors.Wrapf(err, "Expected an int but got %v", v.Value)
			} else {
				return types.Val{
					Tid:   types.IntID,
					Value: i,
				}, nil
			}
		}
	case "float":
		{
			if i, err := strconv.ParseFloat(v.Value, 64); err != nil {
				return types.Val{}, errors.Wrapf(err, "Expected a float but got %v", v.Value)

View on GitHub (pinned to 759e242be6)

Solutions

Validate all variable values are non-empty strings before calling the parse/mutation API with the variables map
Provide a default value for optional variables on the client side
Check where the variables map is populated (env vars, request params) for empty inputs and reject them early

Example fix

// before
vars := map[string]string{"$name": req.Name} // may be ""
// after
if req.Name == "" { return errors.New("$name is required") }
vars := map[string]string{"$name": req.Name}

Defensive patterns

Strategy: validation

Validate before calling

for k, v := range vars {
  if v == "" { return fmt.Errorf("variable %s has empty value", k) }
}

Prevention

Validate the variables map before every parameterized query
Reject empty user/env inputs at the boundary instead of passing them through
Use distinct sentinel handling for optional variables rather than empty strings

When it happens

Trigger: Calling parseValue (reached via ParseWithNeedVars) with a variable map entry whose value is the empty string, e.g. $name="" supplied in the variables map of a parameterized DQL query.

Common situations: Client code builds the variables map from user input or env and the value is unset; template string substitution leaves a variable empty; forgetting to include a required variable so the resolver fills an empty string.

Related errors

AI-assisted analysis of dgraph-io/dgraph@759e242be6 (2026-09-01). Data as JSON: /api/errors/651aadd01a07ac81. Report an issue: GitHub.