Abstract: A master database module is on a master computer node. Slave database modules are on slave computer nodes connected to the master computer node via a network. A distributed database includes executable code executed by processors on the master computer node and the slave computer nodes to receive a distributed database query at the master computer node. A query execution plan is prepared at the master computer node. The query execution plan is deployed on the slave computer nodes. The query execution plan is executed on the slave computer nodes. The slave computer nodes each perform a single node query execution analysis to selectively produce a query cancellation command. The query cancellation command is propagated to the master computer node and the slave computer nodes. The query execution plan is cancelled on the master computer node and the slave computer nodes.

Abstract: This invention provides a system and method for inconspicuously and randomly encoding watermark information into a font encoding vector of document. The invention uses a random number generator to create a key that specifies which indices in the encoding vector should be modified to carry the watermark information. The key may also be used to detect and decode watermarks that were previously embedded into a font encoding vector.

Abstract: A system and method is provided for increasing watermark detection speed and accuracy by using detection information during the detection process. When a source document is watermarked, detection information is determined and stored for later use in the detection process. The detection information can be in any format and includes information about the features of the source document wherein the watermark information is embedded. During detection of watermark values in a non-source document, the watermark detector uses the detection information to determine which of the non-source document features contain the watermark information.

Abstract: A method is provided for watermarking a document using line margin shifting. The method shifts the left margin of lines of text either right or left to encode a watermark in a textual document. To embed the watermark, certain lines of the text are selected to carry watermark information. These lines are shifted either right or left to indicate a 1 or 0.