# Revision history [back]

Hi

This is a limitation of HSQLDB 1.8 engine: A not-null constraint can only be added if the table data for the column has no null values.

So with UI (Right click a table Edit) create without Enry required, then update data (yes/no), then you can add Entry required. Or you can use Tools SQL to execute:

ALTER TABLE "Table name" ADD "Field name" BOOLEAN DEFAULT 0 NOT NULL


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Regards