GD CURRRATE

Коэффициент (курс) перевода из одной валюты в другую.

CREATE TABLE gd_currrate
(
  id             dintkey,
  fromcurr       dintkey,
  tocurr         dintkey,
  fordate        ddate NOT NULL,
  coeff          dcurrrate,
  editiondate    deditiondate
);
 
ALTER TABLE gd_currrate ADD CONSTRAINT gd_pk_currrate
  PRIMARY KEY (id);
 
ALTER TABLE gd_currrate ADD CONSTRAINT gd_uk_currrate
  UNIQUE (fromcurr, tocurr, fordate);
 
ALTER TABLE gd_currrate ADD CONSTRAINT gd_fk1_currrate
  FOREIGN KEY (fromcurr) REFERENCES gd_curr (id) ON UPDATE CASCADE;
 
ALTER TABLE gd_currrate ADD CONSTRAINT gd_fk2_currrate
  FOREIGN KEY (tocurr) REFERENCES gd_curr (id) ON UPDATE CASCADE;
 
ALTER TABLE gd_currrate ADD CONSTRAINT gd_chk1_currrate
  CHECK(fromcurr <> tocurr);