------------------------------------------------------------
Example 1: Tables don't have an PrimayKey

USE db357t;
GO
SELECT SCHEMA_NAME(t.schema_id) AS schema_name
    ,t.name AS table_name
FROM sys.tables t 
WHERE object_id NOT IN 
   (
    SELECT parent_object_id 
    FROM sys.key_constraints 
    WHERE type_desc = 'PRIMARY_KEY_CONSTRAINT' -- or type = 'PK'
    );
GO

------------------------------------------------------------
Example 2: Tables don't have an PrimayKey


USE db357t;
GO
SELECT SCHEMA_NAME(schema_id) AS schema_name
    ,name AS table_name 
FROM sys.tables 
WHERE OBJECTPROPERTY(object_id,'TableHasPrimaryKey') = 0
ORDER BY schema_name, table_name;
GO

------------------------------------------------------------
Example 3: Tables don't have an Index


USE db357t;
GO
SELECT SCHEMA_NAME(schema_id) AS schema_name
    ,name AS table_name
FROM sys.tables 
WHERE OBJECTPROPERTY(object_id,'IsIndexed') = 0
ORDER BY schema_name, table_name;
GO