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POShould I use a unique ID for a row in a junction table?
 

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  1. POShould I use a unique ID for a row in a junction table?
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    <p>I am using SQL Server 2008.</p> <p>A while back, I asked the question "should I use RecordID in a junction table". The tables would look like this:</p> <pre><code>// Images ImageID// PK // Persons PersonID // pk // Images_Persons RecordID // pk ImageID // fk PersonID // fk </code></pre> <p>I was strongly advised NOT to use RecordID because it's useless in a table where the two IDs create a unique combination, meaning there will be no duplicate records. </p> <p>Now, I am trying to find a random record in the junction table to create a quiz. I want to pull the first id and see if someone can match the second id. Specifically, I grab a random image and display it with three possible choices of persons.</p> <p>The following query works, but I've quite a bit of negativity that suggests that it's very slow. My database might have 10,000 records, so I don't think that matters much. I've also read that the values generated aren't truly random. </p> <pre><code>SELECT TOP 1 * FROM Images_Persons ORDER BY newid(); </code></pre> <p>Should I add the RecordID column or not? Is there a better way to find a random record in this case?</p> <p>Previous questions for reference</p> <ul> <li><a href="https://stackoverflow.com/questions/5248816/should-i-use-recordid-as-a-column-name">Should I use &quot;RecordID&quot; as a column name?</a></li> <li><a href="https://stackoverflow.com/questions/7457643/sql-what-is-the-best-table-design-to-store-people-as-musicians-and-artists">SQL - What is the best table design to store people as musicians and artists?</a></li> </ul>
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    1. USEvik James
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    1. COpossible duplicate of [Random record from a database table (T-SQL)](http://stackoverflow.com/questions/191342/random-record-from-a-database-table-t-sql)
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      1. USJahan Zinedine
    2. COThis is perfectly valid.
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      1. USYves M.
    3. COHow exactly do you picture that having a RecordID field will help you getting a random record more efficiently?
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      1. USAdrian Carneiro
 

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