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SDO_SAM.AGGREGATES_FOR_LAYER
Format
Description
Parameters
Usage Notes
SDO_SAM.AGGREGATES_FOR_LAYER(
theme_name IN VARCHAR2,
theme_colname IN VARCHAR2,
aggr_type_string IN VARCHAR2,
aggr_col_string IN VARCHAR2,
tablename IN VARCHAR2,
colname IN VARCHAR2,
dst_spec IN VARCHAR2 DEFAULT NULL
) RETURN SDO_REGAGGRSET;
Computes thematic aggregates for a layer of geometries.
theme_name
Name of the theme table.
theme_colname
Name of the geometry column in theme_name.
SDO_SAM.AGGREGATES_FOR_LAYER
aggr_type_string
Any Oracle SQL aggregate function that accepts one or more numeric values and
computes a numeric value, such as SUM, MIN, MAX, or AVG.
aggr_col_string
Name of a column in theme_name on which to compute aggregate values, as
explained in the Usage Notes. An example might be a POPULATION column.
tablename
Name of the data mining table.
colname
Name of the column in tablename that holds the geometries.
dst_spec
A quoted string specifying either a distance buffer or a number of nearest neighbor
geometries to consider. See the Usage Notes for the SDO_SAM.AGGREGATES_FOR_
GEOMETRY function in this chapter for an explanation of the format and meaning.
For each geometry in tablename, this function identifies the geometries in the
theme_name table, finds their intersection ratio, multiplies the specified aggregate
using this intersection ratio, and aggregates it for each geometry in tablename.
Specifically, for all rows of the theme_name table, it returns the value from the
following function:
SDO_SAM Package (Spatial Analysis and Mining) 29-5