Re: [NOVICE] Conditional constraint?

On Thu, 21 Mar 2002, Nick Haw wrote:

> Sorry it has taken me so long to get back to you but I have been on
> holiday!!!! :o)
>
> OK, here's what I want to do.... The SQL for the table is like this
>
> Table: tblprojectsummary
> CREATE TABLE "tblprojectsummary" (
> "fldpjctno" int4 DEFAULT nextval('tblprojectsummary_fldpjctno_key'::text)
> NOT NULL,
> "fldpjcttitle" varchar(25),
> "fldpjctsummary" text NOT NULL,
> "fldpjcttype" int4,
> "fldpjctclientid" int4,
> "fldpjctclientcontactid" int4,
> "fldpjctcompany" varchar(50) NOT NULL,
> "fldpjctdivision" int4,
> "fldpjctresearchexec" int4 NOT NULL,
> "fldpjctsecresearchexec" int4,
> "fldpjctsubclient" varchar(50),
> "fldpjctsector" varchar(50) NOT NULL,
> "fldpjctresearchtype" varchar(50) NOT NULL,
> "fldpjctpublic" bool,
> "fldpjcttopic" varchar(50) NOT NULL,
> "fldpjctmethod1" varchar(50) NOT NULL,
> "fldpjctmethod2" varchar(50),
> "fldpjctmethod3" varchar(50),
> "fldpjctstatus" varchar(50) NOT NULL,
> "fldpjctpropdate" date NOT NULL,
> "fldpjctpropduedate" date,
> "fldpjctcommdate" date,
> "fldpjctunsuccdate" date,
> "fldpjctunsuccwhy" text,
> "fldpjctfwcommdate" date,
> "fldpjctreportdate" date,
> "fldpjctcompdate" date,
> "fldpjctbudget" float8,
> "fldpjctarea" int4 NOT NULL,
> "fldpjctnotes" text,
> "fldpjctsubcont" bool,
> "fldpjctfolder" varchar(100),
> "fldpjctsuccess" varchar(10),
> "fldpjctweighting" float8,
> "flddateadded" date,
> "flduseradded" varchar(15),
> "flddatemodified" date,
> "fldusermodified" varchar(15);
>
> when someone changes "fldpjctstatus" to a value (ongoing) I want to make
> "fldpjcttitle" NOT NULL. How do I do this?

Maybe a check constraint:
CHECK fldpjctstatus != 'ongoing' or fldpjcttitle IS NOT NULL