What is row set? Explain cached row set in detail.

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 Row set

  • A RowSet is an object that encapsulates a set of rows from either java Database Connectivity (JDBC) result sets or tabular data sources. RowSets support component-based development models like JavaBeans, with a standard set of properties and an event notification mechanism. The support for RowSet was introduced in JDBC 2.0 through the optional packages. However, the implementations of RowSets was standardized in the JDBC RowSet Implementations Specification (JSR-114) by Sun Microsystems, which is available in Java Development Kit (JDK) 5.0. The JDK 5.0 Javadoc provides information about the standard interfaces and base classes for JDBC RowSet implementations.

Catched row set
  •  A CachedRowSet object is a container for rows of data that caches its rows in memory, which makes it possible to operate without always being connected to its data source. 
  • A CachedRowSet object typically contains rows from a result set, but it can also contain rows from any file with a tabular format, such as a spreadsheet. The reference implementation supports getting data only from a ResultSet object, but developers can extend the SyncProvider implementations to provide access to other tabular data sources.
  • An application can modify the data in a CachedRowSet object, and those modifications can then be propagated back to the source of the data.
  • A CachedRowSet object is a disconnected rowset, which means that it makes use of a connection itself with rows and again while it is propagating changes back to its underlying data source. The rest of the time, a CachedRowSet object is disconnected, including while its data is being to its data source only briefly. It connects to its data source while it is reading data to populate modified.
  • A CachedRowSet is a RowSet in which the rows are cached and the RowSet is disconnected, that is, it does not maintain an active connection to the database. 
  • The oracle.jdbc.rowset.OracleCachedRowSet class is the Oracle implementation of CachedRowSet. It can interoperate with the reference implementation of Sun Microsystems. The OracleCachedRowSet class in the ojdbc14.jar file implements the standard JSR-114 interface javax.sql.rowset.CachedRowSet.

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