[QGIS-trac] Re: [Quantum GIS] #1555: A more efficient SQL query for uniqueness

[Quantum GIS]

#1555: A more efficient SQL query for uniqueness
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        Reporter:  gjm                              |         Owner:  nobody
            Type:  enhancement                      |        Status:  new   
        Priority:  minor: annoyance or enhancement  |     Milestone:        
       Component:  Data Provider                    |       Version:  HEAD  
      Resolution:                                   |      Keywords:        
Platform_version:                                   |      Platform:  All   
        Must_fix:  No                               |   Status_info:  0     
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Comment (by jef):

 another candidate:

 {{{
 SELECT NOT EXISTS (SELECT %1 FROM %2.%3 GROUP BY %1 HAVING COUNT(*)>1) as
 isunique;
 }}}

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Ticket URL: <https://trac.osgeo.org/qgis/ticket/1555#comment:2>
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