36.44. sql_features
  The table
  
   sql_features
  
  contains information
   about which formal features defined in the SQL standard are
   supported by
  
   PostgreSQL
  
  .  This is the
   same information that is presented in
  
   Appendix D
  
  .
   There you can also find some additional background information.
 
   
    Table 36.42. 
    
     sql_features
    
    Columns
   
  
| 
        Column Type Description  | 
     
|---|
| 
        
         Identifier string of the feature  | 
     
| 
        
         Descriptive name of the feature  | 
     
| 
        
         Identifier string of the subfeature, or a zero-length string if not a subfeature  | 
     
| 
        
         Descriptive name of the subfeature, or a zero-length string if not a subfeature  | 
     
| 
        
         
          | 
     
| 
        
         Always null, since the PostgreSQL development group does not perform formal testing of feature conformance  | 
     
| 
        
         Possibly a comment about the supported status of the feature  |