StackOverflow2013

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plurals

PO
primarykey
Id
5291174
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2011-03-13T17:42:26.043
FavoriteCount
0
LastActivityDate
2011-03-15T18:19:43.607
LastEditDate
2011-03-15T18:19:43.607
LastEditorUserId
9034
OwnerUserId
588334
ParentId
5288608
PostTypeId
2
Score
2
ViewCount
0
LastEditorDisplayName
text
Body
I would say that if there is a relatively small amount of NULL values, then using NULLs would be okay. However, if you find that most rows contain NULLs, then you might be better off deleting the techDir column and placing a column referencing the "Answers" into a new table alongside another field referencing the "People" table. In other words, create an intermediate table between the Answers table and the People table containing all technical directors as shown below. <img src="https://i.stack.imgur.com/wYcXR.png" alt="enter image description here"> This will get rid of all the NULL values and also allow for more flexibility. If there is only one Technical Director per answer then simply make the column referencing the answers table "Unique" to create a One-to-One relationship. If you need more than one technical director, create a One-to-Many relationship as shown. Another advantage to this design is that it simplifies the query if you ever want to extract all the technical directors. I generally use a simple rule of thumb when deciding whether to use NULL values or not. If I see the table contains lots of NULLS, I remove those columns and create a new table where I can store that data. You should of course also consider the types of queries you will be executing. For example, the design above might require an Inner or Outer Join to view all the rows including the technical directors. As a developer, you should carefully weigh up the pros and cons and look at things like flexibility, speed, complexity and your business rules when making these decisions.
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POForeign key column optionally contains NULL or ID. Is there a better design?
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USHLGEM
UserOwnerUserId
1. USAshraf Abrahams
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. POForeign key column optionally contains NULL or ID. Is there a better design?
 singulars
 PostTypePostTypeId
 PTQuestion
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTAcceptedByOriginator
2. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
3. VO
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 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId
1. This table or related slice is empty.

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