What's the difference in notation for total participation and recursive relation?

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孤城傲影
孤城傲影 2021-01-18 01:31

Does the double line in the following ER diagrams means total participation or recursive relation?

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  •  没有蜡笔的小新
    2021-01-18 02:07

    defination of total participation constraints: the participation of an entoty set E in the eelationship R is said to be a total if every entity in E participates in at least one relationship in R.

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