5 Comments
  1. “CHAR(18) is a red flag. It signals that the data modeler has not assigned a datatype to an attribute or column.” … “Pretty darn clever of those ERwin developers years ago, isn’t it?”

    Respectfully, I disagree. If the tool feels it’s that important to force the user to make a choice, they could have used a blank default, one that is not valid in any target DDL. Then you’d have the guarantee the model could not be realized, and you could even check with a routine whether the model is valid.

    • It is a flag. As you nkow, there might be a better flag. I know a few people who assign Char(-1) as the value since it will fail in database generation. An invalid value is a stronger deterrent to data modeling errors.

  2. Hi, Tom.
    I always big fan of yours, as I mentioned earlier.
    You are right.
    I used Char(9999). Because, it can more easily to find not assigned column.
    And check for naming and datatype by API.
    I compare with standard column in Metadata Systems what predefined naming (include abbreviation) and mapping Domain(Datatype and Default, Valid Value are mapped already to column).
    If exist columns what not applied standard then are exist then this column colored by red automatically.
    And if modeler want to apply to standard then it can be applied automatically by just one click.

    And reset default of null option of column from null to not null and parent null option reset from nulls allow to nulls not allow.
    Because, probability of not null and nulls not allow is much higher then other.

  3. Interesting responses. As a long time ERwin user, I have become trained to look for CHAR(18). Other values are definitely better such as CHAR(-1) but CHAR(18) is the flag that serves me well.

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