One to many table insert in JDBC

Question

hi all, I have an online form when it submit the value will get into three table, one child table is one to many relation to parent , like
parent  table have(     UserId        int Not null,     UniversityN      varchar(10) Not null,   ...   PRIMARY KEY  (UserId)   PaymentId          int Not null  auto_increment ,     UserId        int Not null, ) child Table( PaymentId          int Not null  auto_increment , UserId        int Not null, UniversityN      varchar(10) Not null, record1            varchar(50) Not null, record2            varchar(50) Not null, record13          varchar(50) Not null,     PRIMARY KEY  (PaymentId),     FOREIGN Key(UserId) REFERENCES Parent(UserId) on Delete     Cascade on update cascade)Type=InnoDB DEFAULT CHARSET=utf8; )
then I have
conn.setAutoCommit(false); calstat1 = (CallableStatement) conn.prepareCall(                     "{ call Insert_Parent(?,?,?,?,?,?,?,?,?,?,?,? )}"); calstat2 = (CallableStatement) conn.prepareCall(                     "{ call Insert_ChildRecords(?,?,?,?,?,?,?,?,?,?,?,? )}");
and the UniversityN , recored1, record2, record3 all come from the input form, how can i handle this one to many insert? for each submit the parent table always one row, and the child table is a lease one up to five rows the if the did have five the userId , and UniversityN is same, but the recore 1. record2... is different
thank you

Answer 1

I think you have a problem with your database table definitions that you need to fix before coding java.
In the above, I dont think you need the first PaymentId (in the 'have' table). I also dont think your tables are normalized since I see 'UniversityN' in both the parent and child record. Also, you should rename your tables to something meaningfull rather than 'have' and 'table'. Also, rename the fields better. Ideally get your friendly neighborhood DBA to review your tables. Only when they are well defined should you start to work on java.
Here's an example:
parent  table:
Customer(
    id                number, not null, primary key, must be unique, auto increment
    userId         number, not null, natural key, must be unique
    universityN  varchar(10), Not null
child Table:
Payment(
    id                      number, not null, primary key, must be unique, auto increment
   customer_id        number, not null, foreign key to the customer table's id field
   record1               varchar(50), not null,
   record2               varchar(50), not null,
   record3               varchar(50), not null,
    Cascade on delete record when parent is deleted
    dont cascase update record
)Note: in the above, record1,record2, record3 should probably be put in its own table, with a foreign key back to the payment table.
Note: each table in your database has its own id that is auto generated. Some have a natural key (like userID) that can be used to look up records independent of the auto generated key.
Note the customer_id (foreign key) has the name of table it refers to (customer) and the key its refering to in that table (id).
Note: when you insert a new customer, you need to get the newly generated id. Use the natural key to retreive the id in order to put it in the new payment table's customer_id field.
I suggest you dont cascade delete any child table. Do it programmatically so you can better learn the issues that come up as you insert, update, and delete various parent and child combinations.