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plurals

PO
primarykey
Id
1613138
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2009-10-23T12:30:54.123
FavoriteCount
0
LastActivityDate
2009-10-23T13:57:48.730
LastEditDate
2009-10-23T13:57:48.730
LastEditorUserId
46495
OwnerUserId
46495
ParentId
1613099
PostTypeId
2
Score
7
ViewCount
0
LastEditorDisplayName
text
Body
DISTINCT works globally, on all the columns you SELECT. Here you're getting distinct pairs of (sp_id, company_name) values, but the individual values of each column may show duplicates. That being said, it's extremely deceiving that MySQL authorizes the syntax <code>SELECT DISTINCT(company_name), sp_id</code> when it really means <code>SELECT DISTINCT(company_name, sp_id)</code>. You don't need the parentheses at all, by the way. Edit Actually there's a reason why <code>DISTINCT(company_name), sp_id</code> is valid syntax: adding parentheses around an expression is always legal although it can be overkill: <code>company_name</code> is the same as <code>(company_name)</code> or even <code>(((company_name)))</code>. Hence what that piece of SQL means is really: “DISTINCT [company_name in parentheses], [sp_id]”. The parentheses are attached to the column name, not the DISTINCT keyword, which, unlike aggregate function names, for example, does not need parentheses (<code>AVG sp_id</code> is not legal even if unambiguous for a human reader, it's always <code>AVG(sp_id)</code>.) For that matter, you could write <code>SELECT DISTINCT company_name, (sp_id)</code> or <code>SELECT DISTINCT (company_name), (sp_id)</code>, it's exactly the same as the plain syntax without parentheses. Putting the list of columns inside parentheses – <code>(company_name, sp_id)</code> – is not legal SQL syntax, though, you can only SELECT “plain” lists of columns, unparenthesized (the form's spell-checker tells me this last expression is not an English word but I don't care. It's Friday afternoon after all). Therefore, any database engine should accept this confusing syntax :-(
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POCan't get unique values
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USArthur Reutenauer
UserOwnerUserId
1. USArthur Reutenauer
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
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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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.

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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.