comments in sql server, good or not good for performance?

Is it a good practice to add comments on tables and columns via sp_addextendedproperty ? Someone told me that it will slow the database and it is not worth i开发者_JAVA技巧t. What do you think ?

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Yes, I think it is good practice

No, it doesn't slow performance. Why would it? Does "someone" have empirical proof or an authoritative article?

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It is a great practice to comment the code. Just like coding in a front-end tool, comments are very useful for maintenance & documentation purposes.

Will it slow the "database" down? Absolutely not.

Well, let me correct myself.

Code + Inline Comments only come into play when the engine evaluates and prepares the execution plan.

So the compilation may take a very negligible time to ignore the comments, but that's about it.

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Extended properties will not slow the database and there are automated help tools that will harvest the extended properties to produce documentation for you, very useful.