--1 tips
SELECT NAME FROM SYS.TABLES
EXCEPT
SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE CONSTRAINT_TYPE = 'PRIMARY KEY'
--2 tips
SELECT * FROM SYSOBJECTS A
WHERE XTYPE='U'
AND NOT EXISTS(SELECT 1 FROM SYSOBJECTS WHERE XTYPE='PK' AND PARENT_OBJ=A.ID )
--MySQL
select table_schema,table_name from information_schema.tables
where (table_schema,table_name) not in(
select distinct table_schema,table_name from information_schema.columns where COLUMN_KEY='PRI'
)
and table_schema not in (
'sys','mysql','information_schema','performance_schema'
);