ALTER DOMAIN --> <domain-name> +------------------+---+
                                 +-> IS data-type --+   |
   +----------------------------------------------------+
   +-+-------------------------------+------------------+
     +-> SET DEFAULT value-expr -----+                  |
     +-> DROP DEFAULT ---------------+                  |
   +----------------------------------------------------+
   +-+---------------------------------------------+-+
     +---> COLLATING SEQUENCE IS <collation-name> -+ |
     +---> NO COLLATING SEQUENCE ------------------+ |
   +-------------------------------------------------+
   +--+-----------------------+-+------------------------+->
      +-> domain-constraint --+ ++> sql-and-dtr-clause -++
                                 +----------<-----------+

  data-type =

   -+-> char-data-types -----------------------------------------+-->
    +-> TINYINT --------------+-----+------------+---------------+
    +-> SMALLINT -------------+     +-> ( <n> ) -+               |
    +-> INTEGER --------------+                                  |
    +-> BIGINT ---------------+                                  |
    +-> FLOAT ----------------+                                  |
    +-> NUMBER -+----------------------------------+-------------+
    |           +-> ( -+-> <p> -+-+----------+-> ) +             |
    |                  +-> * ---+ +-> , <d> -+                   |
    +-> LIST OF BYTE VARYING --+------------+--+--------------+--+
    |                          +-> ( <n> ) -+  +-> AS BINARY -+  |
    |                                          +-> AS TEXT ---+  |
    +-> DECIMAL -++------------------------------+---------------+
    +-> NUMERIC -++-> ( --> <n> +----------+-> ) +               |
    |                           +-> , <n> -+                     |
    +-> REAL ----------------------------------------------------+
    +-> DOUBLE PRECISION ----------------------------------------+
    +-> date-time-data-types ------------------------------------+

  char-data-types =

  -+-> CHAR -------------++------------++--------------------------------+-+->
   +-> CHARACTER --------++-> ( <n> ) -++-> CHARACTER SET char-set-name -+ |
   +-> CHAR VARYING -----+                                                 |
   +-> CHARACTER VARYING +                                                 |
   +-> VARCHAR --+> ( <n> ) ---+--------------------------------+----------+
   +-> VARCHAR2 -+             +-> CHARACTER SET char-set-name -+          |
   +-> LONG VARCHAR  ------------------------------------------------------+
   +-> NCHAR --------------+-+------------+--------------------------------+
   +-> NATIONAL CHAR ------+ +-> ( <n> ) -+                                |
   +-> NATIONAL CHARACTER -+                                               |
   +-> NCHAR VARYING --------------+-+------------+------------------------+
   +-> NATIONAL CHAR VARYING ------+ +-> ( <n> ) -+                        |
   +-> NATIONAL CHARACTER VARYING -+                                       |
   +-> RAW -> ( <n> ) -----------------------------------------------------+
   +-> LONG -+--------+----------------------------------------------------+
             +-> RAW -+

  date-time-data-types =

  --+-> DATE -+----------+-----------------+-->
    |         +-> ANSI  -+                 |
    |         +-> VMS ---+                 |
    +-> TIME ---> frac --------------------+
    +-> TIMESTAMP --> frac ----------------+
    +-> INTERVAL ---> interval-qualifier --+

  literal =

  --+-> numeric-literal ----+--->
    +-> string-literal -----+
    +-> date-time-literal --+
    +-> interval-literal ---+

  domain-constraint =

  --+---------------------------------------------+->
    +-> ADD CHECK ( predicate ) NOT DEFERRABLE  --+
    +-> DROP ALL CONSTRAINTS ---------------------+

  sql-and-dtr-clause =

  -+-> QUERY HEADER IS -+> <quoted-string> +------------------+->
   |                    +------ / <--------+                  |
   +-> EDIT STRING IS <quoted-string> ------------------------+
   |                                                          |
   +-> QUERY NAME FOR -+-> DTR --------+-> IS <quoted-string> +
   |                   +-> DATATRIEVE -+                      |
   +-> DEFAULT VALUE FOR -+-> DTR --------+-> IS <literal> ---+
   |                      +-> DATATRIEVE -+                   |
   +-> NO QUERY HEADER ---------------------------------------+
   +-> NO EDIT STRING ----------------------------------------+
   +-> NO QUERY NAME ----+--> FOR -+-> DTR --------+----------+
   +-> NO DEFAULT VALUE -+         +-> DATATRIEVE -+          |
   +-> COMMENT IS -+-> <quoted-string> -+---------------------+
   |               +------ / <----------+                     |
   +-> RENAME TO <new-name> ----------------------------------+