En este artículo, se muestra como obtener información de : ClusteredIndex, Identity y PrimaryKeys en el servidor SQL

SELECT SCHEMA_NAME(schema_id) AS SchemaName,
       name AS TableName,
       OBJECTPROPERTY(object_id, 'TableHasClustIndex')	AS HasClusteredIndex,
       OBJECTPROPERTY(object_id, 'TableHasIdentity')	AS HasIdentity,
       OBJECTPROPERTY(object_id, 'TableHasprimarykey')	AS HasPrimaryKey
FROM sys.tables
ORDER BY 1, 2