Drizzledump not handling MySQL CHAR(0) /VARCHAR(0) columns gracefully

[Patrick Crews]

If a MySQL table has a CHAR 0 column, such as this:
CREATE TABLE char_table(description TEXT,
col_char0 char(0)
) ENGINE=MyISAM;

Drizzledump will produce this output:
CREATE TABLE `char_table` (
  `description` TEXT COLLATE utf8_general_ci DEFAULT NULL,
  `col_char0` VARCHAR COLLATE utf8_general_ci DEFAULT NULL
) ENGINE='InnoDB' COLLATE='utf8_general_ci';

The plain VARCHAR isn't friends with the parser.

[Patrick Crews (patrick-crews)]

Why anyone would use a CHAR(0) column, I dunno. But I figure if one can live on MySQL, we should test for it : ) This is probably very much an edge case though.

[Stewart Smith (stewart)]

On Sat, 04 Dec 2010 01:19:34 -0000, Patrick Crews <email address hidden> wrote:
> Why anyone would use a CHAR(0) column, I dunno. But I figure if one can
> live on MySQL, we should test for it : ) This is probably very much an
> edge case though.

from http://dev.mysql.com/doc/refman/5.0/en/string-type-overview.html

MySQL permits you to create a column of type CHAR(0). This is useful
primarily when you have to be compliant with old applications that
depend on the existence of a column but that do not actually use its
value. CHAR(0) is also quite nice when you need a column that can take
only two values: A column that is defined as CHAR(0) NULL occupies only
one bit and can take only the values NULL and '' (the empty string).

For a start, very Oracle incompatible behaviour :)

--
Stewart Smith

[Patrick Crews (patrick-crews)]

Very cool. I suppose I should've RTFM'd a bit more before I spoke ; )
Thanks for educati-fying me on this.

On Sun, Dec 5, 2010 at 7:11 PM, Stewart Smith <email address hidden>wrote:

> On Sat, 04 Dec 2010 01:19:34 -0000, Patrick Crews <
> <email address hidden>> wrote:
> > Why anyone would use a CHAR(0) column, I dunno. But I figure if one can
> > live on MySQL, we should test for it : ) This is probably very much an
> > edge case though.
>
> from http://dev.mysql.com/doc/refman/5.0/en/string-type-overview.html
>
> MySQL permits you to create a column of type CHAR(0). This is useful
> primarily when you have to be compliant with old applications that
> depend on the existence of a column but that do not actually use its
> value. CHAR(0) is also quite nice when you need a column that can take
> only two values: A column that is defined as CHAR(0) NULL occupies only
> one bit and can take only the values NULL and '' (the empty string).
>
>
> For a start, very Oracle incompatible behaviour :)
>
> --
> Stewart Smith
>
> --
> You received this bug notification because you are a direct subscriber
> of the bug.
> https://bugs.launchpad.net/bugs/685046
>
> Title:
> Drizzledump not handling MySQL CHAR(0) /VARCHAR(0) columns gracefully
>
> Status in A Lightweight SQL Database for Cloud Infrastructure and Web
> Applications:
> Fix Committed
> Status in Drizzle elliott series:
> Fix Committed
>
> Bug description:
> If a MySQL table has a CHAR 0 column, such as this:
> CREATE TABLE char_table(description TEXT,
> col_char0 char(0)
> ) ENGINE=MyISAM;
>
> Drizzledump will produce this output:
> CREATE TABLE `char_table` (
> `description` TEXT COLLATE utf8_general_ci DEFAULT NULL,
> `col_char0` VARCHAR COLLATE utf8_general_ci DEFAULT NULL
> ) ENGINE='InnoDB' COLLATE='utf8_general_ci';
>
> The plain VARCHAR isn't friends with the parser.
>
> To unsubscribe from this bug, go to:
> https://bugs.launchpad.net/drizzle/+bug/685046/+subscribe
>