since you are not creating a flowchart, but er, you must change your palette :) click on the left side of the screen where “flowchart” will be indicated, and select “er”. now use the attribute tool from this new palette. check the properties of this! no underscore ..... but !! primary key: D dia is even semantically correct.
-. "" , "".
er, . , ( x: es). :)
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