Re: alter column to varchar without view drop/re-creation

Emi Lu <emilu@xxxxxxxxxxxxxxxxx> · Fri, 29 Aug 2014 15:09:08 -0400



      Hello list, 

      
      May I know is there a way to "alter column type to varchar"
      (previous is varchar(***)) without view drop/re-creation?

      
      Basically, looking for a way to change column without have to
      drop/re-create dependent views. 

      
      varchar(***) to varchar and no date/numeric changes. 

      
    I saw docs mention about: update pg_attribute. May I know:

    
    . will dependent views updated automatically or there might be
    potential problems?

    . If it's fine, will the following SQL enough to change column from
    varchar(***) to varchar?

    
      update pg_attribute set atttypmod =-1 

      where  attrelid = 'oid' ;

    
    Thanks a lot!

    
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      PostgreSQL 8.3.18 on x86_64