RE: Re: 7.1.2 ERROR: UNIQUE constraint matching given keys for referenced table ......

On Wed, 4 Jul 2001, Lincy Lin wrote:

> Thanks your reply.
>
> Actully, We are using 4 fields (CompanySerialNo, BrahcnOffice,
> DepartmentCategory, Department) to check employee work for which
> company parimary. Well, we have many company here (In Taiwan) have
> multi-company name but in same office. Some employee work for all
> multi-company. But our system only allow one employee belong to one
> company in this time.
>
> Create Table CompanyInfo
> (
>     CompanySerialNo    Char(20)    Parimary Key,
>     LocalName        Text,
>     EnglishName        Text,
>     .............................
>     .............................
> );
>
> Create Table DepartmentInfo
> (
>     CompanySerialNo    Char(20)    References CompanyInfo
>                         On Update Cascade
>                         On Delete Cascade,
>     BranchOffice        Char(40) Default '',
>     DepartmentCategory    Char(40) Default '',
>     Department        Char(40) Default ''
>     /* Primary Key (CompanySerialNo, BranchOffice,
> DepartmentCategory, Department) */ );
>
> Create Table EmployeeInfo
> (
>     EmployeeNo        Char(20)    Primary Key,
>     LocalName        Text,
>     FirstName        Text,
>     LastName        Text,
>     ...........................
>     ...........................
>     CompanySerialNo    Char(20)    References CompanyInfo
>                         On Update Cascade
>                         On Delete Cascade,
>     BranchOffice        Char(40),    /* References DepartmentInfo (BranchOffice)    */
>                         /* On Update Cascade                */
>                         /* On Delete Set Default,                */
>     DepartmentCategory    Char(40),    /* References DepartmentInfo (DepartmentCategory)*/
>                         /* On Update Cascade                */
>                         /* On Delete Set Default,                */
>     Department        Char(40),    /* References DepartmentInfo (Department)        */
>                         /* On Update Cascade                */
>                         /* On Delete Set Default,                */
>     ...........................
>     ...........................
> );
>
>     If
>
>     1. one company don't allow multi-department with same name
>          How to set the references in EmployeeInfo table ?

>
>     2. one company allow multi-department with same name (But not
> with same BranchOffice and/or DepartmentCategory).
>         How to set the references in EmployeeInfo table ?


Okay, since it looks like your key in DepartmentInfo is
>     /* Primary Key (CompanySerialNo, BranchOffice,
> DepartmentCategory, Department) */ );

You should probably make sure the primary key is defined in
DepartmentInfo and do something like

FOREIGN KEY (CompanySerialNo, BranchOffice, DepartmentCategory,
Department) REFERENCES DepartmentInfo

as a table constraint in EmployeeInfo.

>     I think the postgresql from 7.0.3 to 7.1.2 have change some
> basic rule. The old code work fine in 7.0.3 but not ok in 7.1.2.

Yeah, 7.0.3 was technically broken.  The spec requires the unique
constraint, but we didn't check it yet.