How to make two columns in a table together unique?

[pauly]

Hi I learned to make one column in a table unique, for example, using the following statement:

ALTER TABLE “tbl_Certificate” ADD CONSTRAINT MYCONSTRAINT UNIQUE (“Register_No”);

I have checked Hsqldb User Guide . But can not find info on how to make two columns together unique. For example, how to make Last name and First name these two columns together in the table Client unique. Thank you.

[RobertG]

Open the table in Base for editing, not for input data. Go to Tools → Index Design or directly by the button Index Design. A dialog appears. Press New Index. Choose Index Details → Unique and choose the columns, which should be together unique.

[pauly]

Hi Robert, that works like a charm. I didn’t expect it. It is so easy. LibreOffice is lovely! Thank you so much.

[Villeroy]

@pauly

ALTER TABLE “tbl_Certificate” ADD CONSTRAINT MYCONSTRAINT UNIQUE (“Register_No”);

ALTER TABLE "tbl_Certificate" ADD CONSTRAINT MYCONSTRAINT UNIQUE ("Register_No", "Other_Field");

[pauly]

@Villeroy

NIQUE ("Register_No", "Other_Field");

That’s great, Villeroy, thank you for your help.