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[Dmitry Lendel]

ðÒÉ×ÅÔ
CREATE DOMAIN IDUNIQUE AS INTEGER default 0 NOT NULL;

CREATE TABLE CUSTOMER (
    IDKEY         IDUNIQUE,
    constraint pk_Customer primary key (idkey));

CREATE TABLE CASHPAPER (
    IDKEY         IDUNIQUE,
    IDCustomer    integer,
    constraint pk_CASHPAPER primary key (idkey),
    constraint fk_CASHPAPER1 foreign key (IDCustomer) references Customer);

IDCustomer ÄÏÌÖÎÏ ÂÙÔØ not null
÷ÒÏÄÅ ÒÁÎØÛÅ ÔÁËÏÅ ÎÅ ÐÒÏËÁÔÙ×ÁÌÏ, Á 2.0 ÂÅÚ ÐÒÏÂÌÅÍ. ñ ÞÔÏ-ÔÏ ÐÒÏÐÕÓÔÉÌ?

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