syntax error at or near "TYPE"

[eros]

ALTER TABLE public.postcodes
  ALTER COLUMN machi
  TYPE varchar(100);

Error: ERROR: syntax error at or near "TYPE";
Error while executing the query (State:42601, Native Code: 7)

I am using WinSQL, Windows XP SP2 Japanese Version, PostgreSQL 8.x.
I want to alter my machi field from varchar(30) to varchar(100) TYPE.

This is my CREATE TABLE script:

-- Table: public.postcodes

-- DROP TABLE public.postcodes;

CREATE TABLE public.postcodes (
  postcode  varchar(8) NOT NULL,
  post      varchar(6) NOT NULL,
  kencd     varchar(3) NOT NULL,
  ken       varchar(30) NOT NULL,
  shicd     varchar(4) NOT NULL,
  shi       varchar(30) NOT NULL,
  ku        varchar(30),
  machi     varchar(30) NOT NULL,
  status    boolean,
  remarks   text,
  /* Keys */
  CONSTRAINT postcodes_pkey
    PRIMARY KEY (postcode)
) WITHOUT OIDS;

ALTER TABLE public.postcodes
  OWNER TO postgres;

[michaelb]

[CODE=sql]
ALTER TABLE public.postcode s ALTER COLUMN machi
TYPE varchar(100);
[/CODE]

This looks correct, but changing the column datatype was not supported in the versions prior to 8.x.
My first thought is you are running an earlier version of PostgreSQL.

[eros]

This looks correct, but changing the column datatype was not supported in the versions prior to 8.x.
My first thought is you are running an earlier version of PostgreSQL.

I am using PostgreSQL 7.4.1. Is there a documentation that the above scripts are not supported?.

[michaelb]

Of course it is all well documented.
Compare the ALTER TABLE command for 8.2 with that of 7.4 and you'll see the difference.
The commonly used work around is to add a new column, copy the values from the old one, than drop the old column