Oracle SQL 缺少 smth

Question

尝试构建这些表，但总是出现错误或遗漏某些内容，有人可以帮助我吗？ 我正在检查 max_mice 在哪里，它是否在这些值之间并且不起作用，为什么？ 不知道出了什么问题，已经到处搜索，不知道为什么不会创建它们...... 更新：现在我在桌面事件上遇到了问题......

更新：错误是我有：CONSTRAINT fun_maxmi_ch CHECK (200 > max_mice >= min_mice) 而不是下面的代码。

CREATE TABLE Functions (
    function VARCHAR(10) CONSTRAINT fun_fu_pk PRIMARY KEY,
    min_mice NUMBER(3) CONSTRAINT fun_minmi_ch CHECK (min_mice > 5),
    max_mice NUMBER(3),
    CONSTRAINT fun_maxmi_ch CHECK (max_mice >= min_mice and max_mice < 200)
); 

但是创建表时仍然有问题 事件不知道是什么问题！！！

CREATE TABLE Incidents (
    nickname VARCHAR2(15), 
    enemy_name VARCHAR2(15), 
    incident_date DATE CONSTRAINT inc_indate_nn NOT NULL,
    incident_desc VARCHAR2(50),
    CONSTRAINT inc_con_pk PRIMARY KEY (nickname, enemy_name),
    CONSTRAINT inc_nic_fk FOREIGN KEY (nickname) REFERENCES Cats(nickname),
    CONSTRAINT inc_enname_fk FOREIGN KEY (enemy_name) REFERENCES Enemies(enemy_name),
);

这是完整的代码：

CREATE TABLE Enemies (
    enemy_name VARCHAR2(15), 
    hostility_degree NUMBER(2) CONSTRAINT hos_degree_ch CHECK (hostility_degree BETWEEN 1 AND 10),
    species VARCHAR2(15),
    bride VARCHAR2(20),
    CONSTRAINT ene_name_pk PRIMARY KEY(enemy_name)
);

CREATE TABLE Functions (
    function VARCHAR(10) CONSTRAINT fun_fu_pk PRIMARY KEY,
    min_mice NUMBER(3) CONSTRAINT fun_minmi_ch CHECK (min_mice > 5),
    max_mice NUMBER(3),
    CONSTRAINT fun_maxmi_ch CHECK (max_mice >= min_mice and max_mice < 200)
); 

CREATE TABLE Bands (
    Band_no NUMBER(2) CONSTRAINT ban_no_pk PRIMARY KEY,
    name VARCHAR2(20) CONSTRAINT ban_name_nn NOT NULL,
    site VARCHAR2(15) CONSTRAINT ban_site_un UNIQUE,
    band_chief VARCHAR(15) CONSTRAINT ban_chief_un UNIQUE
);


CREATE TABLE Cats (
    name VARCHAR2(15) CONSTRAINT cat_name_nn NOT NULL,
    gender VARCHAR2(1) CONSTRAINT cat_gen_ch CHECK (gender IN('M', 'W')),
    nickname VARCHAR2(15) CONSTRAINT cat_pk PRIMARY KEY,
    function VARCHAR2(10), 
    chief VARCHAR2(15), 
    in_herd_since DATE DEFAULT SYSDATE CONSTRAINT cat_inherd_nn NOT NULL,
    mice_ration NUMBER(3),
    mice_extra NUMBER(3),
    band_no NUMBER(2),
    CONSTRAINT cat_banno_fk FOREIGN KEY (band_no) REFERENCES Bands(band_no),
    CONSTRAINT cat_chief_fk FOREIGN KEY (chief) REFERENCES Cats(nickname),
    CONSTRAINT cat_fun_fk FOREIGN KEY (function) REFERENCES Functions(function)
);

ALTER TABLE Bands 
ADD CONSTRAINT ban_chief_fk FOREIGN KEY (band_chief) REFERENCES Cats(nickname);


CREATE TABLE Incidents (
    nickname VARCHAR2(15), 
    enemy_name VARCHAR2(15), 
    incident_date DATE CONSTRAINT inc_indate_nn NOT NULL,
    incident_desc VARCHAR2(50),
    CONSTRAINT inc_con_pk PRIMARY KEY (nickname, enemy_name),
    CONSTRAINT inc_nic_fk FOREIGN KEY (nickname) REFERENCES Cats(nickname),
    CONSTRAINT inc_enname_fk FOREIGN KEY (enemy_name) REFERENCES Enemies(enemy_name),
);

Answer 1

这是 max_mice 我正在检查它是否在这些值之间并且不起作用为什么？

当涉及到代码中的第一个表时，Functions，问题在于最后一个检查约束的声明：

    max_mice NUMBER(3) CONSTRAINT fu_maxmi_ch CHECK (200 > max_mice >= min_mouse)

问题：

• 不支持双重不等式条件
• 需要在表级别而不是列级别声明多列检查约束

这有效：

CREATE TABLE Functions (
    function VARCHAR(10) CONSTRAINT fu_fu_pk PRIMARY KEY,
    min_mice NUMBER(3) CONSTRAINT fu_minmi_ch CHECK (min_mice > 5),
    max_mice NUMBER(3),
    CONSTRAINT fu_maxmi_ch CHECK (max_mice >= min_mice and max_mice < 200)
); 

注意：我不建议将列命名为function，因为它显然与 SQL 关键字冲突。