52.65. pg_available_extensions
  The
  
   pg_available_extensions
  
  view lists the
   extensions that are available for installation.
   See also the
  
   
    pg_extension
   
  
  catalog, which shows the extensions currently installed.
 
   
    Table 52.66. 
    
     pg_available_extensions
    
    Columns
   
  
| Name | Type | Description | 
|---|---|---|
       
        name
       
       | 
      
       
        name
       
       | 
      Extension name | 
       
        default_version
       
       | 
      
       
        text
       
       | 
      
       Name of default version, or
       
        NULL
       
       if none is
       specified
       | 
     
       
        installed_version
       
       | 
      
       
        text
       
       | 
      
       Currently installed version of the extension,
       or
       
        NULL
       
       if not installed
       | 
     
       
        comment
       
       | 
      
       
        text
       
       | 
      Comment string from the extension's control file | 
  The
  
   pg_available_extensions
  
  view is read only.