anchor.diff:      : NULL | NOT NULL | UNIQUE KEY? | primaryKey | COMMENT STRING_
       ;
   
  +dataTypeGenerated_
  +    : (GENERATED ALWAYS)? AS expr (VIRTUAL | STORED)? dataTypeGeneratedOption_*
  +    ;
  +
   defaultValue_
       : NULL | NUMBER_ | STRING_ | currentTimestampType_ (ON UPDATE currentTimestampType_)? | ON UPDATE currentTimestampType_
       ;
  
positive.code:     ;
  
  createDefinition_
      : columnDefinition | constraintDefinition | indexDefinition_ | checkExpr_
      ;
  
  columnDefinition
  
negative.code:     : columnName (LP_ NUMBER_ RP_)? (ASC | DESC)?
      ;
  
  checkConstraintDefinition_
      : (CONSTRAINT ignoredIdentifier_?)? CHECK expr (NOT? ENFORCED)?
      ;
  
  createLike_
  