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https://issues.apache.org/jira/browse/ACCUMULO-1228?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13622374#comment-13622374
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Josh Elser commented on ACCUMULO-1228:
--------------------------------------

Perhaps that would satisfy the requirement. Ultimately, I want a client to be 
able to just say "Give me these columns!". My thought was that "well, a client 
may know of columns from many ways". Hypothetically, 

{noformat}
fetchColumns(new Column[] {new Column("c1"), new Column("c2"), new 
LocalityGroup("lg1")})
{noformat}

>From an interface perspective, having something like a scan profile, which 
>would encompass the collection of columns regardless of how one might define 
>that collection of columns, would satisfy my want from the API and, it seems, 
>avoid concerns about the mutability of locality groups and unaware clients. 
>Perhaps a happy medium would be to work towards being able to fetch data using 
>a collection of columns to fetch (using *only* the column name, not locality 
>group) or using a scan profile which could create a short-hand for clients to 
>include/exclude many columns. I think I like that idea.
                
> Allow clients to disable column families and locality groups
> ------------------------------------------------------------
>
>                 Key: ACCUMULO-1228
>                 URL: https://issues.apache.org/jira/browse/ACCUMULO-1228
>             Project: Accumulo
>          Issue Type: New Feature
>          Components: client, tserver
>    Affects Versions: 1.5.0
>            Reporter: William Slacum
>            Priority: Minor
>             Fix For: 1.6.0
>
>
> There's an inconsistency between what a server is capable of and what a 
> client can tell it to do with respect to fetching column families.
> Currently, a user can tell a {{Scanner}} to fetch some set of column 
> families. The iterators support not only this, but also the converse where a 
> user does not want to retrieve column families. An iterator implementation 
> can do this by hand, but a client cannot specifically tell a Scanner to not 
> return data from a set of column families. Clients should be able to specify 
> this option.
> There also seems to be an inconsistency with how locality groups are defined 
> and then utilized. If I want to specify a set of column families as being 
> part of a locality group, I have to provide a mapping of locality group name 
> to a list of column families. If I want to fetch a locality group, I have to 
> get the mapping first, rather than just set which locality group I want to 
> use. It'd be more convenient to tell the scanner just to fetch which locality 
> groups I want, and have the server know which column families that means.

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