Marko asked for a simple way to have ENUM columns in I_S.

This task will introduce helper classes, so a ENUM will be declared as simply as follows:

static const LEX_CSTRING io_values[]=

{

  STRING_WITH_LEN("IO_NONE"),

  STRING_WITH_LEN("IO_READ"),

  STRING_WITH_LEN("IO_WRITE"),

  STRING_WITH_LEN("IO_PIN")

};

static TypelibBuffer<4> io_values_typelib(io_values);

A definition of a column using the above ENUM declaration will look about like this:

  Column("IO_FIX", Enum(&io_values_typelib), NULLABLE),

This task will change INFORMATION_SCHEMA.INNODB_BUFFER_PAGE.IO_FIX from VARCHAR(64) to ENUM.