如何在hsql create table中使用外键？ [英] how to use foreign-keys with hsql create table?

问题描述

有人可以解释一下如何在hsql中使用外键吗？
我想在创建表中使用它，但是工作alter table也可以。
我没有工具，只是在月食中
hsql代码出了什么问题？

could someone explain me how to use foreign keys in hsql? I would like it in an create table, but working alter table is also ok. I am working without tools, just in eclipse whats wrong with the hsql code?

CREATE TABLE user(
  t_id INTEGER GENERATED BY DEFAULT AS IDENTITY(START WITH 1, INCREMENT   BY   1) PRIMARY KEY,
  name VARCHAR(30),
  lastname VARCHAR(30),
  email  VARCHAR(30),  
  --FOREIGN KEY (b_id) REFERENCES bookingnumber(b_id)
);

CREATE TABLE bookingnumber (
  b_id INTEGER PRIMARY KEY
);

ALTER TABLE user
  ADD FOREIGN KEY (fk_b_id) REFERENCES bookingnumber(b_id);

推荐答案

也许您正在尝试将每个预订号链接到一个用户。在这种情况下，每个用户可能存在多个预订号。如果要执行此操作，请在BOOKINGNUMBER表中添加一列T_ID并在此表上创建外键。

Perhaps you are trying to link each booking number to a user. In this case, multiple booking numbers may exist for each user. If you want to do this, add a column T_ID to the BOOKINGNUMBER table and created the foreign key on this table.

但是您的声明是将每个用户链接到预订号并且没有正确的语法。它需要USER表中名为B_ID的列才能工作。语法将是这样的：

But your statement is linking each user to a booking number and doesn't have the correct syntax. It needs a column named B_ID in the USER table to work. And the syntax would be like this:

ALTER TABLE user ADD FOREIGN KEY (b_id) REFERENCES bookingnumber(b_id);

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