Which statement is needed to revise?

问题

I tried to create several tables, but only the server table was created. Please fix my work!

CREATE TABLE server 
(
SERVER_ID       varchar(25) NOT NULL,
SERVER_IP       varchar(15)     NOT NULL,
SERVER_LOCATION     varchar(25)     NOT NULL,
SERVER_BRAND    varchar(15)     NOT NULL,
CONSTRAINT server_pk
PRIMARY KEY (SERVER_ID)
);

CREATE TABLE application
(
APP_ID          varchar(25) NOT NULL,
ACCOUNT_NUM varchar(25)     NOT NULL,
RECORD_ID       varchar(10)     NOT NULL,
VERSION_ID      varchar(10)     NOT NULL,
LAST_UPDATED        date        NOT NULL,
CONSTRAINT application_pk
PRIMARY KEY (APP_ID),
CONSTRAINT application _fk_account
FOREIGN KEY (ACCOUNT_NUM)   
REFERENCES account (ACCOUNT_NUM),
CONSTRAINT application _fk_record
FOREIGN KEY (RECORD_ID)         
REFERENCES record (RECORD_ID)
);

CREATE TABLE record
(
RECORD_ID       varchar(25) NOT NULL,
VIN_NUM         varchar(25)     NOT NULL,
SERVER_ID       varchar(25)     NOT NULL,
CONSTRAINT record_pk
PRIMARY KEY (RECORD_ID, VIN_NUM, SERVER_ID),
CONSTRAINT record_fk_vehicle
FOREIGN KEY (VIN_NUM)   
REFERENCES vehicle (VIN_NUM),
CONSTRAINT record_fk_server
FOREIGN KEY (SERVER_ID)
REFERENCES server (SERVER_ID)
);

CREATE TABLE vehicle
(
VIN_NUM     varchar(25) NOT NULL,
V_MILEAGE       int         NOT NULL,
V_GASUSED       varchar(25)     NOT NULL,
V_ELECTRICALMILES   int         NOT NULL,
DRIVER_ID       varchar(25) NOT NULL,
CONSTRAINT vehicle_pk
PRIMARY KEY (VIN_NUM),
CONSTRAINT vehicle_fk_driver
FOREIGN KEY (DRIVER_ID) 
REFERENCES driver (DRIVER_ID)
);

CREATE TABLE driver
(
DRIVER_ID       varchar(25) NOT NULL,
LICENSE_NUM     varchar(25) NOT NULL,
FIRST_NAME      varchar(25) NOT NULL,
LAST_NAME       varchar(25)     NOT NULL,
INSURANCE_POLICY    varchar(25) NOT NULL,
ACCOUNT_NUM int     NOT NULL,
CONSTRAINT driver_pk
PRIMARY KEY (DRIVER_ID),
CONSTRAINT driver_fk_account
FOREIGN KEY (ACCOUNT_NUM)   
REFERENCES account (ACCOUNT_NUM)
);

CREATE TABLE account
(
ACCOUNT_NUM int     NOT NULL,
DRIVER_ID       varchar(25) NOT NULL,
DEVICE_ID       varchar(25) NOT NULL,
DATE_CREATED        date        NOT NULL,
ACCOUNT_STATUS  varchar(10) NOT NULL,
CONSTRAINT account_pk
PRIMARY KEY         (ACCOUNT_NUM, DRIVER_ID),
CONSTRAINT account_fk_driver
FOREIGN KEY (DRIVER_ID)     
REFERENCES driver (DRIVER_ID)
);

回答1:

There are several issues here.

You should create tables in order that matches foreign key constraint dependencies, i.e. you can't create detail table first, and then its master table because there's no table (or its primary key) which is to be referenced.

A good workaround for that is to remove foreign key constraints from create table and create them separately (using alter table ... add constraint) after all tables are created.

There's no problem if two tables reference each other (such as driver and account do), if there's a good reason to do it. However, as I previously said - you can't do it within create table statements; at least one foreign key has to be moved out.

If primary key consists of several columns (so it is a composite key), foreign key also must contain the same number & datatypes of columns that reference it. That's what you have for driver and account tables.

account's primary key is (account_num, driver_id)
driver's foreign key can't be just (account_num) - it has to contain driver_id as well

Finally, application table: its foreign keys can't be created because it references

account table whose primary key is (account_num, driver_id), but - application doesn't contain driver_id column at all which might mean that you wrongly set account's primary key (or application table)
record table which has a composite primary key on (record_id, vin_num, server_id), while application has only record_id. Remark I wrote for account is valid here as well

Now, if we fix what I mentioned, tables are created, but application misses all its foreign key constraints.

SQL> CREATE TABLE server
  2  (
  3  SERVER_ID       varchar2(25) NOT NULL,
  4  SERVER_IP       varchar2(15)     NOT NULL,
  5  SERVER_LOCATION     varchar2(25)     NOT NULL,
  6  SERVER_BRAND    varchar2(15)     NOT NULL,
  7  CONSTRAINT server_pk
  8  PRIMARY KEY (SERVER_ID)
  9  );

Table created.

SQL>
SQL> CREATE TABLE driver
  2  (
  3  DRIVER_ID       varchar2(25) NOT NULL,
  4  LICENSE_NUM     varchar2(25) NOT NULL,
  5  FIRST_NAME      varchar2(25) NOT NULL,
  6  LAST_NAME       varchar2(25)     NOT NULL,
  7  INSURANCE_POLICY    varchar2(25) NOT NULL,
  8  ACCOUNT_NUM int     NOT NULL,
  9  CONSTRAINT driver_pk
 10  PRIMARY KEY (DRIVER_ID)
 11  --CONSTRAINT driver_fk_account
 12  --FOREIGN KEY (ACCOUNT_NUM)
 13  --REFERENCES account (ACCOUNT_NUM)
 14  );

Table created.

SQL>
SQL> CREATE TABLE account
  2  (
  3  ACCOUNT_NUM int     NOT NULL,
  4  DRIVER_ID       varchar2(25) NOT NULL,
  5  DEVICE_ID       varchar2(25) NOT NULL,
  6  DATE_CREATED        date        NOT NULL,
  7  ACCOUNT_STATUS  varchar2(10) NOT NULL,
  8  CONSTRAINT account_pk
  9  PRIMARY KEY         (ACCOUNT_NUM, DRIVER_ID),
 10  CONSTRAINT account_fk_driver
 11  FOREIGN KEY (DRIVER_ID)
 12  REFERENCES driver (DRIVER_ID)
 13  );

Table created.

SQL>
SQL> alter table driver add constraint driver_fk_account
  2  foreign key (account_num, driver_id)
  3  references account (account_num, driver_id);

Table altered.

SQL>
SQL> CREATE TABLE vehicle
  2  (
  3  VIN_NUM     varchar2(25) NOT NULL,
  4  V_MILEAGE       int         NOT NULL,
  5  V_GASUSED       varchar2(25)     NOT NULL,
  6  V_ELECTRICALMILES   int         NOT NULL,
  7  DRIVER_ID       varchar2(25) NOT NULL,
  8  CONSTRAINT vehicle_pk
  9  PRIMARY KEY (VIN_NUM),
 10  CONSTRAINT vehicle_fk_driver
 11  FOREIGN KEY (DRIVER_ID)
 12  REFERENCES driver (DRIVER_ID)
 13  );

Table created.

SQL>
SQL> CREATE TABLE record
  2  (
  3  RECORD_ID       varchar2(25) NOT NULL,
  4  VIN_NUM         varchar2(25)     NOT NULL,
  5  SERVER_ID       varchar2(25)     NOT NULL,
  6  CONSTRAINT record_pk
  7  PRIMARY KEY (RECORD_ID, VIN_NUM, SERVER_ID),
  8  CONSTRAINT record_fk_vehicle
  9  FOREIGN KEY (VIN_NUM)
 10  REFERENCES vehicle (VIN_NUM),
 11  CONSTRAINT record_fk_server
 12  FOREIGN KEY (SERVER_ID)
 13  REFERENCES server (SERVER_ID)
 14  );

Table created.

SQL>
SQL> CREATE TABLE application
  2  (
  3  APP_ID          varchar2(25) NOT NULL,
  4  ACCOUNT_NUM varchar2(25)     NOT NULL,
  5  RECORD_ID       varchar2(10)     NOT NULL,
  6  VERSION_ID      varchar2(10)     NOT NULL,
  7  LAST_UPDATED        date        NOT NULL,
  8  CONSTRAINT application_pk
  9  PRIMARY KEY (APP_ID)
 10  --CONSTRAINT application_fk_account
 11  --FOREIGN KEY (ACCOUNT_NUM)
 12  --REFERENCES account (ACCOUNT_NUM),
 13  --CONSTRAINT application_fk_record
 14  --FOREIGN KEY (RECORD_ID)
 15  --REFERENCES record (RECORD_ID)
 16  );

Table created.

SQL>

回答2:

You have to add a / after every table definition end -

CREATE TABLE server 
(
SERVER_ID       varchar(25) NOT NULL,
SERVER_IP       varchar(15)     NOT NULL,
SERVER_LOCATION     varchar(25)     NOT NULL,
SERVER_BRAND    varchar(15)     NOT NULL,
CONSTRAINT server_pk
PRIMARY KEY (SERVER_ID)
);
/         ---->   Here
CREATE TABLE application
(
APP_ID          varchar(25) NOT NULL,
.....

来源：https://stackoverflow.com/questions/60996247/which-statement-is-needed-to-revise

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sql

Oracle