Databases
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    1. This table or related slice is empty.
    1. POHow is introspection useful?
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    1. USSenthil Kumaran
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    1. POHow is introspection useful?
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      1. This table or related slice is empty.
      1. VTUpMod
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    1. COHi. Thank you for your reply. One thing that confuses me about this is maybe you are expecting (and have written code to reflect this expectation) that if an object wants to get a user's ID, this would be done with a function called "getUserID()". And in your code, you introspect and look for this function called getUserID. Well, maybe the programmer prefers to name his functions "differently" and calls his function "retrieve_the_user_identification_integer()" or something wacky like that. This is what confuses me about on the fly introspection. It seems that you are assuming a lot.
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      1. USChris D.
    2. COActually, yours is good doubt. You normally don't introspect on the objects created by you or your class. Because, you already know that something is present! Now, consider the cases where objects are **given** to you and you don't know much information about them, introspection is for those cases. Good example. You write a GUI Editor with Autocompletion, I use the editor and I create a custom module and object. When I try to auto-complete an object which I wrote, your editor should give me the list of possible functions. How will your editor know? By introspecting my objects. HTH.
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      1. USSenthil Kumaran
    3. COThe concept of "duck typing" is relevant here. If an object has a `write()` method, Python will be happy to let you use it anywhere you are trying to write a file -- regardless of whether it is derived from the `file` class. (This is very different from some other languages!) So if you are about to write to a file, you can either give it a whirl and see if you get an exception, or you can check to see if it has a `write()` method using `hasattr()` first. The usual Python idiom is in fact to try it and catch exceptions, but there are situations where "looking before you leap" is also useful.
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      1. USkindall
 

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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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