prestodb/presto · error · PrestoException

NOT_FOUND

NOT_FOUND

Error message

Function namespace not found: %s

What it means

createFunction validates that the function's parent namespace (catalog.schema) exists in the MySQL-backed manager before inserting. If functionNamespaceDao.functionNamespaceExists returns false, it throws NOT_FOUND because functions cannot be created in an unregistered namespace.

Source

Thrown at presto-function-namespace-managers/src/main/java/com/facebook/presto/functionNamespace/mysql/MySqlFunctionNamespaceManager.java:160

    protected ScalarFunctionImplementation fetchFunctionImplementationDirect(SqlFunctionHandle functionHandle)
    {
        checkCatalog(functionHandle);
        Optional<SqlInvokedFunction> function = functionNamespaceDao.getFunction(hash(functionHandle.getFunctionId()), functionHandle.getFunctionId(), getLongVersion(functionHandle));
        return sqlInvokedFunctionToImplementation(function.orElseThrow(() -> new InvalidFunctionHandleException(functionHandle)));
    }

    @Override
    public void createFunction(SqlInvokedFunction function, boolean replace)
    {
        checkCatalog(function);
        checkFunctionLanguageSupported(function);
        checkArgument(!function.hasVersion(), "function '%s' is already versioned", function);

        QualifiedObjectName functionName = function.getFunctionId().getFunctionName();
        checkFieldLength("Catalog name", functionName.getCatalogName(), MAX_CATALOG_NAME_LENGTH);
        checkFieldLength("Schema name", functionName.getSchemaName(), MAX_SCHEMA_NAME_LENGTH);
        if (!functionNamespaceDao.functionNamespaceExists(functionName.getCatalogName(), functionName.getSchemaName())) {
            throw new PrestoException(NOT_FOUND, format("Function namespace not found: %s", functionName.getCatalogSchemaName()));
        }
        checkFieldLength("Function name", functionName.getObjectName(), MAX_FUNCTION_NAME_LENGTH);

        if (function.getParameters().size() > MAX_PARAMETER_COUNT) {
            throw new PrestoException(GENERIC_USER_ERROR, format("Function has more than %s parameters: %s", MAX_PARAMETER_COUNT, function.getParameters().size()));
        }
        for (Parameter parameter : function.getParameters()) {
            checkFieldLength("Parameter name", parameter.getName(), MAX_PARAMETER_NAME_LENGTH);
        }

        checkFieldLength(
                "Parameter type list",
                function.getFunctionId().getArgumentTypes().stream()
                        .map(TypeSignature::toString)
                        .collect(joining(",")),
                MAX_PARAMETER_TYPES_LENGTH);
        checkFieldLength("Return type", function.getSignature().getReturnType().toString(), MAX_RETURN_TYPE_LENGTH);

View on GitHub (pinned to 55bb57d202)

Solutions

1. Create/register the function namespace (catalog.schema) in the MySQL store first, then retry createFunction.
2. Correct the catalog/schema names in the function definition.
3. Verify namespace rows with the dao or SQL query functionNamespaceExists uses.
4. Add a preflight check in deployment tooling that provisions missing namespaces.

Example fix

// before
manager.createFunction(function, false); // namespace missing
// after
functionNamespaceDao.insertFunctionNamespace(catalog, schema); // provision first
manager.createFunction(function, false);

if (!functionNamespaceDao.functionNamespaceExists(catalog, schema)) {
    provisionNamespace(catalog, schema); // or abort
}

try {
    manager.createFunction(function, false);
} catch (PrestoException e) {
    if (isNotFound(e)) { provisionNamespace(catalog, schema); manager.createFunction(function, false); } else { throw e; }
}

When it happens

Trigger: Calling createFunction(function) whose functionId's qualified object name references a catalog/schema pair with no row in the function_namespace table.

Common situations: Typo in catalog or schema name of the function definition; namespace never created for this catalog; deploying functions to a new catalog before provisioning its namespace row.

Understand the failure class

Background: NOT_FOUND error code: why tRPC, Harbor, Nacos and other libraries return 404 "not found" errors for resources that may still exist — this error's family across 11 libraries.

Related errors

• GENERIC_USER_ERROR
• NOT_FOUND
• NOT_FOUND
• NOT_FOUND
• NOT_FOUND

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/35a1ffbc35bdf6b6. Report an issue: GitHub.