Abstract: A method and apparatus are provided for avoiding target database constraint violations in a database replication system. The database replication system includes a source database and a target database, wherein target database transactions automatically abort due to constraint violations. Each database has one or more tables and at least one of the target database tables has one or more constraints. The database replication system replicates source database transactions. For each target database transaction corresponding to a replicated source database transaction, changes made at the source database are replicated to the target database. When it is detected that a replicated change causes a constraint violation as a result of one or more of the target database tables having one or more constraints, the applying of the database change to the target database of the database change is deferred and the database change is posted to an electronic list.

Abstract: An automated method and apparatus are provided for comparing a source database and a target database that are intended to be kept in synchronization with each other. An application processes database changes that are posted to the source database and replicated to the target database. The source database and the target database are made up of blocks of data. Blocks of data from the source database having database changes are collected. These blocks of data are replicated to the target database. Blocks of data from the target database that correspond to the blocks of data from the source database having database changes are read. Representations of the blocks of data from the source database having database changes are compared to representations of blocks of data from the target database that correspond to the blocks of data from the source database having database changes.

Abstract: A method and apparatus are described for continuously sampling a process stream, or reservoir of aqueous cellulosic pulp and detecting oversize contaminants in the sampled stream. This serves the overall objective of estimating the level of contamination in the process stream or reservoir during a given period of production; the method may include the following stages: 1) a continuous sample stream is drawn from the process or main stream, 2) the stream is passed through a centrifugal device which divides the sampled stream according to density, 3) the stream with the higher level of contaminants from the centrifugal device is passed to a screen which isolates the contaminants, and 4) the contaminants are flushed from the screen so that they can be quantified; these measurements are used to assess the purity of the material being produced. One useful application of this invention is to assess the presence of trace amounts of plastic contaminants in the production of the cellulosic pulp.