Mailing List
Home
MySQL General - General MySQL discussion
MaxDB - Everything about MaxDB, formerly known as SAP DB
MySQL on Win32 - Runing MySQL on Windows 9x/Me/NT/2000/XP
Java Help - Mostly related to the MySQL Connector/J driver
ODBC - ODBC with the MySQL Connector/ODBC driver
Perl - Perl support for MySQL with DBI and DBD::mysql
MySQL++ - Programming with the C++ API to MySQL
Subjects
• mysql openssl Question
• mysql:it 's a db not a dbms how it 's possible?!
• Does the binary log enabling affect the MySQL performances?
• Strange behavior, Table Level Permission
• FULLTEXT query format question
• Preventing Duplicate Entries
• Comparing and writing out BLOBS
• Executing MySQL Commands From Within C Program
• Can 't access mysql after kernel upgrade
• Mysql 4 0 Oracle Stored Procedure Trigger Conversion
• Downgrade Mysql from 4 to 3 23
• MySQL Cluster Software
• mysql test 4 1 fails with the gis test
• ERROR 2002: Can 't connect to local MySQL server through socket
• Getting Identity after INSERT
• Update one field with more fields from another table
• ERROR 1045: Access denied for user: 'root@localhost ' (Using
password: NO)
• mysql have same function mthod as Oracle decode()
 
Search:  
Power your search with and, or, +, -, or "some phrase" operators.
EJB - Entity Beans

EJB - Entity Beans

2004-06-09       - By Boyd E. Hemphill

 Back
Reply:     1     2  

All:

First let me say I know only the most basic of Java stuff.

I am working with a Java colleague on the development of a data model
(MySQL of course :-) and we seem to run into the problem an Entity Beans
cannot support joins. Can anyone tell me if this is true (If so, what
use are they for any sort of complex data model?). If no, can you send
me some information on how to implement a join with the Beans and some
possible resources to consult?

My naïvet? leads me to believe I should be able to create a container of
beans that is the result of any query I can write against the DB. Or
something like this anyway!

Please help!

Thanks for your time.

Best Regards,
Boyd E. Hemphill
bhemphill@(protected)
Triand, Inc.
www.triand.com
O: (512) 248-2287
M: (713) 252-4688
-- --Original Message-- --
From: Sudip Shekhawat [mailto:sudip_s_s@(protected)]
Sent: Wednesday, June 09, 2004 2:33 PM
To: mysql@(protected)
Subject: Foreign Key on text field

Hi,

I am using MySQL 4.0.17. When I try to create a foreign key on a field
of
the type text, I get this error:

040609 15:02:31 Error in foreign key constraint of table
db_name/tb_name:
There is no index in the table db_name/tb_name where the columns appear
as the first columns. Constraint:
FOREIGN KEY (CEA_key) REFERENCES relation (CEA_key) ON DELETE CASCADE
)TYPE=InnoDB;


Can I create a foreign key on the text field?? In the parent table the
parent column has a index of length 64.

Thanks
Sudip

__ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ ____ __
Looking to buy a house? Get informed with the Home Buying Guide from MSN

House & Home. http://coldwellbanker.msn.com/


--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe:
http://lists.mysql.com/mysql?unsub=bhemphill @(protected)



--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/mysql?unsub=mysql @(protected)