[postgis-devel] Regular raster blocking (was: Real extent feature lost after metadata as views)

[Mateusz Loskot]

On 7 December 2012 15:33, Sandro Santilli <strk at keybit.net> wrote:
> On Fri, Dec 07, 2012 at 01:25:32PM +0000, Mateusz Loskot wrote:
>> On 6 December 2012 18:32, Pierre Racine <Pierre.Racine at sbf.ulaval.ca> wrote:
>> >
>> > The regular_blocking constraint for a raster coverage (or raster table) is set to TRUE if and only if the following conditions are fulfilled:
>> >
>> > 1) All rasters (or tiles) have the same SRID, scale_x, scale_y, skew_x, skew_y, number of band and all the
>> > corresponding bands (having the same band number) have the same pixel types and nodata values.
>> >
>> > 2) All rasters (or tiles) have their upper left corners aligned on a grid defined by the upper left corner of the coverage (or table) global extent and the block sizes.
>> >
>> > 3) All rasters (or tiles) have their width equal to blocksize_x and their height equal to blocksize_y.
>>
>> I agree with all the three points. (I snipped the details).
>
> Where's the exception to (3) gone ?
> The one aimed at allowing no padding, which started this whole thread ?

In the course of  discussion, we have decided what follows:

1) we allow tilesize < blocksize exception for tiles located in the
last row and column
of the tiled raster grid

2) thus, padding is no longer required

3) but, padding is allowed and optional, and left to the discretion of
user loading data
who is assumed to be aware about the resulting change in spatial extent.

Best regards,
--
Mateusz Loskot, http://mateusz.loskot.net