This glossary describes Sybase Replication Agent terms used in this book.
The basic database server in the Sybase Client-Server architecture. It manages multiple databases and multiple users, tracks the actual location of data on disks, maintains mapping of logical data description to physical data storage, and maintains data and procedure caches in memory. See also Open Server and Replication Server.
A materialization method that copies subscription data from a primary to a replicate database in a single atomic operation. No changes to primary data are allowed until subscription data is captured. Atomic materialization is the default method for the Replication Server create subscription command. See also nonatomic materialization and bulk materialization.
A bulk copy transfer utility that provides the ability to load multiple rows of data into a table in a target database. See also bulk copy.
An Open Client interface for the high-speed transfer of data between a database table and program variables. It provides an alternative to the use of SQL insert and select commands to transfer data.
A materialization method whereby subscription data in a replicate database is initialized outside of the replication system. Bulk materialization involves a series of commands, starting with define subscription. You can use bulk materialization for subscriptions to table replication definitions or function replication definitions. See also atomic materialization and nonatomic materialization.
In client/server systems, the part of the system that sends requests to servers and processes the results of those requests.
Software that is responsible for the user interface, including menus, data entry screens, and report formats. See also client.
An instruction to the DBMS to make permanent the changes requested in a transaction. See also transaction. Contrast with rollback.
The process of copying data to remote locations. The copied (replicated) data is then kept synchronized with the primary data. Data replication is distinct from data distribution. Replicated data is stored copies of data at particular sites throughout a system and is not necessarily distributed data. Contrast with data distribution. See also transaction replication.
A server that provides the functionality necessary to maintain the physical representation of a table in a database. Data servers are usually database servers, but they can also be any data repository with the interface and functionality Replication Server requires.
A collection of data with a given structure for accepting, storing, and providing data for multiple users.
A connection that allows a Replication Server to manage the database and distribute transactions to the database. Each database in a replication system can have only one database connection. See also Replication Server and route.
A keyword that identifies the characteristics of stored information on a computer. Some common datatypes are: char, int, smallint, date, time, numeric, and float. Different data servers support different datatypes.
A computer-based system for defining, creating, manipulating, controlling, managing, and using databases. The database management system can include the user interface for using the database, or it can be a stand-alone database system. Compare with RDBMS.
A Replication Server object that represents a data server operation such as insert, delete, or begin transaction. Replication Server distributes these operations from primary to replicate databases as functions. Each function consists of a function name and a set of data parameters. When a function is to be applied, Replication Server uses function strings to convert a function to a command or set of commands for a type of database. See also function string.
A string that Replication Server uses to map a function and its parameters to a data server API. For the rs_select and rs_select_with_lock functions only, the string contains an input template, used to match function strings with the database command. For all other functions, the string also contains an output template, used to format the database command for the destination data server.
Connectivity software that allows two or more computer systems with different network architectures to communicate.
One Replication Server in a replication system is the ID Server. In addition to performing the usual Replication Server tasks, the ID Server assigns unique ID numbers to every Replication Server and database in the replication system, and maintains version information for the replication system.
A stable queue used to spool messages from a Replication Agent to a Replication Server. The inbound queue is under the control of Replication Server.
A file containing information that Sybase Open Client/Open Server applications need to establish connections to other Open Client/Open Server applications. The interfaces file name varies by platform: interfaces for UNIX platforms, sql.ini for Microsoft Windows NT and Windows 95, and win.ini for Windows 3.x.
An interactive SQL client application that can connect and communicate with any Sybase Open Server application, including SQL Server or Adaptive Server.
An object-oriented programming language developed by Sun Microsystems. A “write once, run anywhere” programming language.
A communication protocol for database-independent connectivity between Java clients and data servers.
A software development environment for writing applets and applications in Java.
The Java Runtime Environment consists of the Java Virtual Machine, the Java Core Classes, and supporting files. See also Java Virtual Machine.
The part of the Java Runtime Environment (JRE) responsible for interpreting Java byte codes. See also JRE (Java Runtime Environment).
A computer network located on the user’s premises and covering a limited geographical area. Communication within a local area network is not subject to external regulations; however, communication across the LAN boundary can be subject to some form of regulation. Contrast with WAN.
The time it takes to distribute a transaction from a primary database to a replicate database.
A type of data element associated with a column in a table that contains extremely large quantities of data (often more than 1 gigabyte).
A component of Replication Agent that interacts with the primary data server to capture transactions marked for replication. See also Log Transfer Interface and Log Transfer Manager.
A component of Replication Agent that interacts with Replication Server. The Log Transfer Interface sends LTL to the primary Replication Server so it can distribute replicated transactions. See also Log Reader and Log Transfer Manager.
A component of Replication Agent that interacts with other Replication Agent components to control and coordinate Replication Agent operations. See also Log Reader and Log Transfer Interface.
A data server login name that Replication Server uses to maintain replicate data. See also Replication Server.
A Sybase Replication Agent system table. The marked objects table is a user table in the primary database, created by a script generated by the Sybase Replication Agent. The marked objects table contains a row for each object marked for replication in the primary database. See also Replication Agent.
The process of copying data specified by a subscription from a primary database to a replicate database, thereby initializing the replicate table, and activating the subscription so that Replication Server can begin replicating data to the replicate database. See also atomic materialization, bulk materialization, and non-atomic materialization.
A materialization method that copies subscription data without a lock on the primary database. Changes to the primary table are allowed during data transfer, which may cause temporary inconsistencies between replicate and primary databases. Nonatomic materialization is an optional method for the Replication Server create subscription command. Contrast with atomic materialization. See also bulk materialization.
A standard communication protocol for clients connecting to database servers.
A Sybase product that provides customer applications, third-party products, and other Sybase products with the interfaces needed to communicate with Open Server applications.
A Sybase product that provides the tools and interfaces required to create a custom server.
A stable queue used to spool messages. The Data Server Interface outbound queue spools messages to a replicate data server. The Replication Server Interface outbound queue spools messages to a replicate Replication Server.
The version of a set of data in a replicated data system from which replication occurs. With Sybase Replication Agent, primary data is stored in Informix Dynamic Server. See also Replication Agent and Replication Server.
A quiescent replication system is one in which all updates have been propagated to their destinations. Some Replication Server commands or procedures require that you first quiesce the replication system.
In the context of Sybase Replication Agent, when the Replication Agent instance is quiescent, it is in the Admin state.
The application that controls relational databases. Compare with DBMS. See also relational database.
A collection of data in which data is viewed as being stored in tables consisting of columns (data items) and rows (units of information). Relational databases can be accessed by SQL requests. See also SQL.
Any database that contains data that is replicated from another database via the replication system. See also primary database and Replication Server.
A table that is maintained by Replication Server, in part or in whole. There is one primary version of the table, which is marked for replication; all other versions are replicated copies. See also Replication Server.
A program or thread that transfers transaction log information representing changes made to primary data from a database server to a Sybase Replication Server for distribution to other (replicate) databases.
Usually, a description of a table for which subscriptions can be created. The replication definition, maintained by Replication Server, includes information about the columns to be replicated and the location of the primary version of the table. See also Replication Server and subscription.
The Sybase server program that maintains replicated data on a LAN and processes data transactions received from other Replication Servers on the same LAN or on a WAN. See also SQL Server.
The Adaptive Server or SQL Server database containing a Replication Server's system tables. See also Replication Server and SQL Server.
A data processing system where data is replicated in multiple databases to provide remote users with the benefits of local data access. Specifically, a replication system that is based upon Replication Server and includes other components such as Replication Agents and data servers.
An instruction to a database to back out of the changes requested in a unit of work (called a transaction). Contrast with commit. See also transaction.
A one-way message stream from a primary Replication Server to a replicate Replication Server. Routes carry data modification commands (including those for RSSDs) and replicated functions or stored procedures between Replication Servers. See also Replication Server.
A non-procedural programming language used to process data in a relational database. ANSI SQL is an industry standard. See also SPL.
A store-and-forward queue in which Replication Server messages destined for a route or database connection are stored. Messages written into the stable queue remain there until they can be delivered to the replicate Replication Server or replicate database. See also database connection, Replication Server, and route.
A request for Replication Server to maintain a replicated copy of a table, or a set of rows from a table, in a replicate database at a specified location. See also replication definition and Replication Server.
The method that ensures primary and replicate tables are equivalent. For example, if transaction number 100 is successful in the primary database, the 100th transaction in the replicate database should also be successful.
In a relational DBMS, a two-dimensional array of data or a named data object that contains a specific number of unordered rows composed of a grouping of columns specific for the table. See also database.
A group that can include zero, one, or many database operations (including inserts, updates, and deletes) that are applied or rejected as a whole. Each SQL statement that modifies data is considered a transaction.
Generally, the log of transactions that affect the data managed by a database server.
Sybase Replication Agent creates a transaction log that consists of tables, stored procedures, and triggers in the primary database. The Replication Agent Log Reader component reads the transaction log to identify the changes to marked tables in the primary database. See also Replication Server.
A condition in which all transactions in the primary database are applied in the replicate database in the same order that they were applied in the primary database.
A Replication Server user-defined function is a function that you create. A user-defined function is a custom-built Replication Server function whose name and parameters exactly match the name and parameters of a replicated stored procedure. See also function and function string.
