Suppose you have 3 tables: TABHDBH, TABHDBHCHUYEN and TABHDBHCT
Table TABHDBH has the following fields:
NGAY DateTime;
IDHDBH int
...

Table IDHDBHCT has the following fields:
MAHDBH int
...

TABHDBHCHUYEN
NGAYCHUYEN datetime
MAHDBH int
...

RELATIONSHIP OF 3 TABLE
TABHDBHCHUYEN.MAHDBH head n
TABHDBH.IDHDBH head 1
TABHDBHCT.MAHDBH head n
Code:
DELETE T1
FROM TABHDBHCHUYEN T1
INNER JOIN TABHDBH T2 ON T1.MAHDBH = T2.IDHDBH INNER JOIN
           TABHDBHCT T3 ON T2.IDHDBH = T3.MAHDBH
WHERE (CONVERT(VARCHAR, NGAYCHUYEN, 101) <= '01/07/2017')
When running the query without error only delete the 1 record in TABHDBHCHUYEN and the records in the other 2 TABLE not delete record, you see help me wrong? Created a relational table for 3 tables to Delete Rule mode to Cascade but not delete.