Derby 如何在现有列上添加 NOT NULL 约束

Question

I have been searching for solutions to this, all what I have seen doesn't work, currently I am trying: ALTER TABLE INVOICE_RECORDS ALTER COLUMN SERIAL_NUMBER VARCHAR(10) NOT NULL but it doesn't work.

Error message is: java.sql.SQLSyntaxErrorException: Syntax error: Encountered "VARCHAR" at line 1, column 53.

I am running this in a JavaFX app.

I just want to add the NOT NULL constraint to the SERIAL_NUMBER column.

Answer 1

Based on Bryan Pendleton's comment I tried

ALTER TABLE INVOICE_RECORDS ALTER COLUMN SERIAL_NUMBER NOT NULL

...and it worked for me. Removing VARCHAR(10) did the trick.

Thanks Bryan!

Answer 2

TutorialsPoint说要这样做：

ALTER TABLE INVOICE_RECORDS MODIFY SERIAL_NUMBER VARCHAR(10) NOT NULL

Answer 3

尝试这个。

ALTER TABLE INVOICE_RECORDS ADD CONSTRAINT INVOICE_SERIAL_NUM NOT NULL(SERIAL_NUMBER);