创建SQL表时，出现此错误“错误代码30000，SQL状态42X01：语法错误：在第3行，第22列遇到了“ AUTO_INCREMENT”。

Question

CREATE TABLE Products
(
Item_ID int NOT NULL AUTO_INCREMENT,
item_make varchar(255) NOT NULL,
item_model varchar(255),
brought_in_date varchar(255),
collected_date varchar(255),
whats_wrong varchar(255),
what_was_done varchar(255),
Price varchar(255),
CID varchar(255),
PRIMARY KEY (Item_ID),
FOREIGN KEY (CID) REFERENCES Customers(CID)
)

When I execute this I get this error

  Error code 30000, SQL state 42X01: Syntax error: Encountered "AUTO_INCREMENT" at line 3, column 22.

I am using sql on the java database, derby

Does anyone know what I did wrong.

Answer 1

Instead of AUTO_INCREMENT (which is MySQL dialect), you should use the SQL standard GENERATED ALWAYS AS IDENTITY as supported by Derby:

CREATE TABLE Products
(
Item_ID int GENERATED ALWAYS AS IDENTITY not null primary key,
item_make varchar(255) NOT NULL,
item_model varchar(255),
brought_in_date varchar(255),
collected_date varchar(255),
whats_wrong varchar(255),
what_was_done varchar(255),
Price varchar(255),
CID varchar(255),
FOREIGN KEY (CID) REFERENCES Customers(CID)
)

Answer 2

Accordign to the Derby definition table page the syntax would be something like this:

 CREATE TABLE PRODUCTS
 (
 ITEM_ID INTEGER NOT NULL GENERATED ALWAYS AS IDENTITY (START WITH 1,  INCREMENT BY 1)
 ...
 UNIQUE (MAP_ID)
 )

Link here derby docs