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Writer Overview

The Oracle Spatial writer module stores geometric, raster, point cloud, and attribute data in an Oracle Spatial database. Only uppercase table names are supported.

The Oracle Spatial writer provides the following capabilities:

Transaction Support: The Oracle Spatial writer provides transaction support that eases the data loading process. Occasionally, a data load operation terminates prematurely due to data difficulties. The transaction support provides a mechanism for reloading corrected data without data loss or duplication.
Table Creation: The Oracle Spatial writer uses the information within the FME mapping file to automatically create database tables as needed. If the relational model of storing geometry is used, the writer will create and populate all needed supporting tables. In such a case, the <layername>, <layername>_SDOGEOM, <layername>_SDOLAYER, <layername>_SDOINDEX, and <layername>_SDODIM tables will all be created. Creation of related tables is also supported, such as the Raster Data Table (RDT) for GeoRaster columns, or the block table for Point Cloud columns. Metadata tables and triggers are also created accordingly.
Table Dropping: The Oracle Spatial writer has an option that allows each table to be written to be dropped if recreating, or truncated if appending. Metadata information is updated using triggers for rasters and it is replaced on write for geometry. Likewise, related tables, such as RDTs for GeoRaster columns or block tables for point cloud columns, will be dropped when empty. Metadata tables are updated via DML triggers, however the triggers themselves are not currently dropped.
Index Creation: The Oracle Spatial writer will set up and populate all needed indexes and index tables as part of the loading process. For the relational model, indexes on SDO_GID columns in the <layername> and <layername>_SDOGEOM tables are created, and a compound index on the SDO_GID and SDO_CODE columns in the <layername>_SDOINDEX is created. The <layername>_SDOINDEX table will also be populated.
Bulk Loading: The Oracle Spatial writer uses a bulk loading technique to ensure speedy data load.
Raster Interleaving: Raster data can be written using Band SeQuential (BSQ), Band Interleaved by Line (BIL) or Band Interleaved by Pixel (BIP) interleaving. The default interleaving is BSQ.
Raster Pyramid Generation: Native pyramid generation can optionally be performed as a post-process once writing is complete. Number of levels and the resampling type can be optionally specified.
Raster Validation: Native validation can optionally be performed as a post-process once writing is complete.
Raster Compression: Native DEFLATE, JPEG-B and JPEG-F compression can optionally be performed as a post-process once writing is complete.

Repeatedly reading and saving files may decrease the quality for this format. In addition, Workbench may not know which format data comes from, and whether it used lossy compression. If you know that source data comes from files with lossy compression, you should also set the compression level to 0. Although this compression still does not guarantee the exact copy of the source file, the output will be very close to the original.