Databases
StackOverflow2013
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PO
 

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    <p>The problem is with comparisons between the keys you are storing in the <code>Dictionary</code> and the keys you are trying to look up.</p> <p>When you add something to a <code>Dictionary</code> or access the indexer of a <code>Dictionary</code> it uses the <code>GetHashCode()</code> method to get a hash value of the key. The hashcode for a <code>Tuple</code> is unique to that instance of the <code>Tuple</code>. This means that unless you are passing in the exact same instance of the <code>Tuple</code> class into the indexer, it will not find the previously stored value. Your usage of <code>mergedDict[Tuple.Create(...</code> creates a brand new Tuple with a different hash code than is stored in the <code>Dictionary</code>.</p> <p>I would recommend creating your own class to use as the key and implementing <code>GetHashCode()</code> and the Equality methods on that class. That way the Dictionary will be able to find what you previously stored there.</p> <p>More: The reason this is confusing to a lot of people is that for something like <code>String</code> or <code>Int32</code>, <code>String.GetHashCode()</code> will return the same hash code for two different instances that have the same value. A more specialized class such as <code>Tuple</code> doesn't always work the same. The implementor of <code>Tuple</code> could have gotten the hash code of each input to the <code>Tuple</code> and added them together (or something), but running Tuple through a decompiler you can see that this is not the case.</p>
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    1. This table or related slice is empty.
    1. POSystem.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary
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    1. USKevin Kalitowski
    1. USKevin Kalitowski
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    1. This table or related slice is empty.
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    1. POSystem.Collections.Generic.KeyNotFoundException: The given key was not present in the dictionary
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      1. This table or related slice is empty.
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      1. This table or related slice is empty.
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      1. This table or related slice is empty.
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    1. COThank you very much for your help.
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      1. USProgramming Newbie
    2. COIf you use ReSharper, you can press Alt+Ins and have it generate all of the GetHashCode(), Equals(), etc methods for you. They still need a little manual work but it saves a lot of time.
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      1. USKevin Kalitowski
 

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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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