Re: Difficulty modelling sales taxes

On Mon, Jan 2, 2017 at 6:29 AM, Frank Millman <frank(at)chagford(dot)com> wrote:

>
> *From:* amul sul
> *Sent:* Monday, January 02, 2017 12:42 PM
> *To:* Frank Millman
> *Cc:* pgsql-general
> *Subject:* Re: [GENERAL] Difficulty modelling sales taxes
>
> > On Mon, Jan 2, 2017 at 4:03 PM, Frank Millman <frank(at)chagford(dot)com>
> wrote:
> >
> > Hi all
> >
> >
> >
> > It is a bit ugly, because I have to use the ‘NVARCHAR code’ column from
> >
> > tax_codes, not the primary key, but I think it would work.
> >
> >
> >
> NVARCHAR ? Are you using PostgreSQL as database server?
> >
>
>
> Oops, sorry.
>
> I am testing with PostgreSQL and with SQL Server, so I was in the wrong
> mindset when I posted.
>
> I should have said VARCHAR.
>
> Frank
>
>
>
>

*First, there is no need to make row_id's when you already have a valid
primary key.Next, DO NOT begin object names with underscores.So try this
model instead:CREATE TABLE tax_categories ( tax_category VARCHAR() NOT
NULL, description VARCHAR() NOT NULL, CONSTRAINT tax_cats_pk PRIMARY
KEY (tax_category) ); CREATE TABLE tax_codes ( tax_category VARCHAR()
NOT NULL, code VARCHAR() NOT NULL, description VARCHAR() NOT NULL,
CONSTRAINT tax_codes_pk PRIMARY KEY (tax_category, code), CONSTRAINT
tax_category_fk (tax_category) FOREIGN KEY REFERENCES tax_categories
(tax_category) );CREATE INDEX idx_tax_category ON tax_codes USING
BTREE (tax_category); CREATE INDEX idx_code ON tax_codes USING BTREE
(code);-- *

*Melvin DavidsonI reserve the right to fantasize. Whether or not you wish
to share my fantasy is entirely up to you. *