ST_NumBands — 返回光栅对象中的波段数。
integer ST_NumBands(raster rast);
integer ST_NumBands(
)
返回光栅对象中的波段数。
SELECT rid, ST_NumBands(rast) As numbands FROM dummy_rast; rid | numbands ----+---------- 1 | 0 2 | 3
ST_Value