From: Sandro Santilli Date: Wed, 3 Sep 2014 09:11:56 +0000 (+0000) Subject: Add documentation for {Add,Drop}OverviewConstraints (#2824) X-Git-Tag: 2.2.0rc1~866 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=d719b294f07f104bb57fdba1c0ba367773108a58;p=postgis Add documentation for {Add,Drop}OverviewConstraints (#2824) git-svn-id: http://svn.osgeo.org/postgis/trunk@12934 b70326c6-7e19-0410-871a-916f4a2858ee --- diff --git a/doc/reference_raster.xml b/doc/reference_raster.xml index 222febc8c..863a6949d 100644 --- a/doc/reference_raster.xml +++ b/doc/reference_raster.xml @@ -800,6 +800,171 @@ SELECT srid, scale_x, scale_y, blocksize_x, blocksize_y, num_bands, pixel_types, + + + + AddOverviewConstraints + + Tag a raster column as being an overview of another. + + + + + + + boolean AddOverviewConstraints + name + ovschema + name + ovtable + name + ovcolumn + name + refschema + name + reftable + name + refcolumn + int + ovfactor + + + + boolean AddOverviewConstraints + name + ovtable + name + ovcolumn + name + reftable + name + refcolumn + int + ovfactor + + + + + + + Description + + +Adds constraints on a raster column that are used to display information +in the raster_overviews raster catalog. + + +The ovfactor parameter represents the scale multiplier +in the overview column: higher overview factors have lower resolution. + + +When the ovschema and refschema +parameters are omitted, the first table found scanning the +search_path will be used. + + + Availability: 2.0.0 + + + + Examples + + +CREATE TABLE res1 AS SELECT +ST_AddBand( + ST_MakeEmptyRaster(1000, 1000, 0, 0, 2), + 1, '8BSI'::text, -129, NULL +) r1; + +CREATE TABLE res2 AS SELECT +ST_AddBand( + ST_MakeEmptyRaster(500, 500, 0, 0, 4), + 1, '8BSI'::text, -129, NULL +) r2; + +SELECT AddOverviewConstraints('res2', 'r2', 'res1', 'r1', 2); + +-- verify if registered correctly in the raster_overviews view -- +SELECT o_table_name ot, o_raster_column oc, + r_table_name rt, r_raster_column rc, + overview_factor f +FROM raster_overviews WHERE o_table_name = 'res2'; + ot | oc | rt | rc | f +------+----+------+----+--- + res2 | r2 | res1 | r1 | 2 +(1 row) + + + + + See Also + + + , + , + + + + + + + + DropOverviewConstraints + + Untag a raster column from being an overview of another. + + + + + + + boolean DropOverviewConstraints + name + ovschema + name + ovtable + name + ovcolumn + + + + boolean AddOverviewConstraints + name + ovtable + name + ovcolumn + + + + + + + Description + + +Remove from a raster column the constraints used to show it as +being an overview of another in the raster_overviews +raster catalog. + + +When the ovschema parameter is omitted, +the first table found scanning the search_path +will be used. + + + Availability: 2.0.0 + + + + See Also + + + , + , + + + + diff --git a/doc/using_raster_dataman.xml b/doc/using_raster_dataman.xml index fb7671a12..8d08af97c 100644 --- a/doc/using_raster_dataman.xml +++ b/doc/using_raster_dataman.xml @@ -495,7 +495,7 @@ Available GDAL raster formats: Raster Overviews - raster_overviews catalogs information about raster table columns used for overviews and additional information about them that is useful to know when utilizing overviews. Overview tables are cataloged in both raster_columns and raster_overviews because they are rasters in their own right but also serve an additional special purpose of being a lower resolution caricature of a higher resolution table. These are generated along-side the main raster table when you use the -l switch in raster loading. + raster_overviews catalogs information about raster table columns used for overviews and additional information about them that is useful to know when utilizing overviews. Overview tables are cataloged in both raster_columns and raster_overviews because they are rasters in their own right but also serve an additional special purpose of being a lower resolution caricature of a higher resolution table. These are generated along-side the main raster table when you use the -l switch in raster loading or can be generated manually using . Overview tables contain the same constraints as other raster tables as well as additional informational only constraints specific to overviews. The information in raster_overviews does not duplicate the information in raster_columns. If you need the information about an overview table present in raster_columns you can join the raster_overviews and raster_columns together to get the full set of information you need. Two main reasons for overviews are: