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    Type:
Task
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    Resolution: Done
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    Priority:
Major - P3
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    Affects Version/s: None
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    Component/s: Diagnostics, Index Maintenance
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Add startup warnings for any invalid (indexes which can no longer be created) index spec. so users know they have an issue.
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SERVER-12242 can't run "compact" on a collection if it has an index on an empty field name
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 - Closed
 
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SERVER-12244 can't run reIndex() on collection if it contains an index key with an empty field
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 - Closed
 
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SERVER-11374 Can create indexes on non-insertable fields (i.e. beginning with '$')
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 - Closed
 
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SERVER-8391 Pre-flight upgrade tool to check for changes breaking backwards compatibility or introducing regressions
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 - Closed
 
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SERVER-10857 Improve error checking of text index spec and text-indexed documents
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 - Closed
 
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SERVER-11812 Can create indexes on invalid fields (empty, $** component)
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 - Closed
 
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