-- clauses

ADD, ADD COLUMN,
ALTER,
DROP, DROP COLUMN,
SET, SET ( .. ),
ON,
    ACCESS METHOD,
    AGGREGATE,
    ATTRIBUTE,
    CASCADE,
    COLLATION,
    COLUMN,
    CONFLICT,
    CONSTRAINT,
    CONVERSION,
    DATABASE,
    DEFAULT,
    DOMAIN,
    EVENT TRIGGER,
    EXTENSION,
    EVENT TRIGGER,
    FOREIGN DATA WRAPPER,
    FOREIGN TABLE,
    FROM CURRENT,
    FUNCTION,
    IDENTITY,
    INDEX,
    ISOLATION LEVEL SERIALIZABLE, ISOLATION LEVEL REPEATABLE READ,
        ISOLATION LEVEL READ COMMITTED, ISOLATION LEVEL READ UNCOMMITTED,
    LARGE OBJECT,
    LOGGED, UNLOGGED,
    MAPPING FOR .. WITH .., MAPPING REPLACE .. WITH .., 
    MATERIALIZED VIEW,
    NOT VALID,
    OPERATOR,
    OPERATOR CLASS .. USING ..,
    OPERATOR FAMILY .. USING ..,
    POLICY,
    PROCEDURAL LANGUAGE,
    PROCEDURE,
    PUBLICATION,
    READ WRITE, READ ONLY,
    RESTRICT,
    ROLE,
    ROUTINE,
    RULE,
    SCHEMA,
    SEQUENCE,
    SERVER,
    STATISTICS,
    STORAGE PLAIN, STORAGE EXTERNAL, STORAGE EXTENDED, STORAGE MAIN,
    SUBSCRIPTION,
    TABLE,
    TABLESPACE,
    TEXT SEARCH CONFIGURATION,
    TEXT SEARCH DICTIONARY,
    TEXT SEARCH PARSER,
    TEXT SEARCH TEMPLATE,
    TRANSFORM FOR .. LANGUAGE SQL,
    TRIGGER,
    TYPE,
    VALUE,
    VIEW,
    WITH OIDS, WITHOUT OIDS,
    WITHOUT CLUSTER,
SET DATA TYPE;