Peter T Mount wrote:
> Quoting Joe Conway <[EMAIL PROTECTED]>:
>
> > TEXT is a datatype which stores character data of unspecified length (up
> > to
> > the max value of a 4 byte integer in length, although I've seen
> > comments
> > indicating that the practical limit is closer to 1 GB -- not sure why).
>
> It may be something to do with the 1Gb splitting of the physical files
> representing a table... Unless it changed recently, a table was split over
> multiple files at the 1Gb mark.

    No,  it's  because  the  upper  two bits of the variable size
    field are used as flags.

    But in practice there are other limits that force you to keep
    the objects you throw into text or bytea fields alot smaller.
    When your INSERT query is received,  parsed,  planned  and  a
    heap  tuple  created,  there are at least four copies of that
    object in the backends memory. How much virtual  memory  does
    your OS support for one single process?

    And  by  the  way,  TOAST is not only used for character data
    types.  All variable size data types in the base  system  are
    toastable. Well, arrays might be considered sort of pop-tarts
    here, but anyway, they get toasted.


Jan

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