Philip Walden wrote:
> Michael Stassen wrote:
>
>>
>> Philip Walden wrote:
>>
>>> Michael Stassen wrote:
>>>
>>>> You need supp_cd to be first in an index. Try
>>>>
>>>> ALTER TABLE hpi_supp_agmt ADD INDEX supp_ind (supp_cd);
>>>>
>>>> then try to add your foreign key constraint again.
>>>>
>>>> Michael
>>>>
>>> Looks like that does not work. BTW this does work (without adding a
>>> separate index) in postgres.
>>>
>>> mysql> alter table hpi_supp_agmt add index i1hpisuppagmt (supp_cd);
>>>
>>> Query OK, 28635 rows affected (4.89 sec)
>>>
>>> Records: 28635 Duplicates: 0 Warnings: 0
>>
>> OK, now table hpi_supp_agmt has supp_cd first in the i1hpisuppagmt
>> index, and table supp has supp_cd first in the p1supp primary key
>> index, so supp_cd should now be a foreign key candidate.
>>
>>> mysql> alter table hpi_supp_agmt add constraint f1hpisuppagmt
>>> foreign key (hpi_no) references hpi;
>>>
>>> ERROR 1005 (HY000): Can't create table './gem/#sql-c3f_2.frm' (errno:
>>> 150)
>>
>> But here you try to add a foreign key constraint using hpi_no, which
>> is not first in any index. And what is hpi? Did you try your
>> original statement?
>>
>>> alter table hpi_supp_agmt add constraint foreign key (supp_cd)
>>> references supp(supp_cd);
>>
>> I would expect this to work now. At least, it does for me.
>>
>> Michael
>
> You're right, I guess I was getting a bit punchy that late at night.
>
> However, when I go back and try the correct ALTER statement:
>
> mysql> alter table hpi_supp_agmt add constraint foreign key (supp_cd)
> references supp(supp_cd);
> ERROR 1216 (23000): Cannot add or update a child row: a foreign key
> constraint fails
>
> It still fails :-(
This error means what it says. There is at least one row in
hpi_supp_agmt with a value in supp_cd that does not exist in supp. You
should be able to find these problem rows with something like
SELECT h.div_cd, h.hpi_no, h.supp_cd, h.agmt_no FROM hpi_supp_agmt AS h
LEFT JOIN supp AS s ON (h.supp_cd = s.supp_cd)
WHERE s.supp_cd IS NULL;
> Could be that the primary index is first in the create table statement
> and it is hiding the index with just supp_cd in it?
I don't think so. If mysql didn't see the index somehow, you'd get the
same error as before.
> mysql> show create table hpi_supp_agmt;
>
> | hpi_supp_agmt | CREATE TABLE `hpi_supp_agmt` (
>
> `div_cd` char(4) NOT NULL default '',
>
> `hpi_no` char(15) NOT NULL default '',
>
> `supp_cd` char(5) NOT NULL default '',
>
> `agmt_no` char(8) NOT NULL default '',
>
> `agmt_owner` char(4) NOT NULL default '',
>
> `agmt_price` decimal(16,0) NOT NULL default '0',
>
> `agmt_uom` char(4) NOT NULL default '',
>
> `agmt_lt` int(11) NOT NULL default '0',
>
> `agmt_exp_dt` date NOT NULL default '0000-00-00',
>
> `updt_user_id` smallint(6) NOT NULL default '0',
>
> `updt_dt` date NOT NULL default '0000-00-00',
>
> `create_dt` date NOT NULL default '0000-00-00',
>
> PRIMARY KEY (`div_cd`,`hpi_no`,`supp_cd`,`agmt_no`),
>
> KEY `i1hpisuppagmt` (`supp_cd`)
>
> ) TYPE=InnoDB DEFAULT CHARSET=latin1 |
>
> Phil
>
Michael
