A Lucidchart alternative — for database diagrams

CREATE TABLE organizations (
    id          bigserial    PRIMARY KEY,
    name        varchar(160) NOT NULL,
    created_at  timestamptz  NOT NULL DEFAULT now()
);

CREATE TABLE users (
    id         bigserial    PRIMARY KEY,
    org_id     bigint       NOT NULL REFERENCES organizations(id),
    email      varchar(255) NOT NULL UNIQUE,
    role       varchar(20)  NOT NULL DEFAULT 'member'
);
COMMENT ON COLUMN users.role IS 'owner, admin or member';

CREATE TABLE plans (
    id            bigserial    PRIMARY KEY,
    code          varchar(40)  NOT NULL UNIQUE,
    monthly_usd   numeric(8,2) NOT NULL,
    seat_limit    int
);
COMMENT ON COLUMN plans.seat_limit IS 'NULL means unlimited seats';

CREATE TABLE subscriptions (
    id          bigserial   PRIMARY KEY,
    org_id      bigint      NOT NULL REFERENCES organizations(id),
    plan_id     bigint      NOT NULL REFERENCES plans(id),
    started_on  date        NOT NULL,
    ends_on     date
);
COMMENT ON COLUMN subscriptions.ends_on IS 'NULL while the subscription is active';

CREATE TABLE invoices (
    id               bigserial     PRIMARY KEY,
    subscription_id  bigint        NOT NULL REFERENCES subscriptions(id),
    amount           numeric(10,2) NOT NULL,
    issued_on        date          NOT NULL,
    paid_on          date
);