If you want to import a raster dataset into a geodatabase, see About loading and importing rasters. This help topic covers loading and importing rasters as well as loading rasters into an empty raster dataset.
To mosaic raster datasets together, see Mosaicking raster datasets.
If you are working with raster catalogs, refer to Creating raster catalogs in a geodatabase. This topic discusses raster catalogs in geodatabases and how to create them.
