1.1.1

Table Of Contents
list-partitioning
A partitioning strategy based on specied lists of values of one or more elds. For example, a table could be
list-partitioned on a string-valued eld such that all the values for a specied list of string values are placed in
the same bucket.
locator
A locator facilitates discovery of all members in a distributed system. This is a component that maintain a registry
of all peer members in the distributed system at any given moment. Though typically started as a separte process
(with redundancy for HA), this can also be embedded in any peer member (like a Fabric Server). This opens a
TCP port and all new members connect to this process to get the initial membership information. Learn more
about the GemFire distributed system including locators distributed system.
partitioned table
A table that manages large volumes of data by partitioning it into manageable chunks and distributing it across
all the servers in its hosting server group. Partitioning attributes, including the partitioning strategy can be
specied by supplying a PARTITION BY clause in a CREATE TABLE statement. See also replicated table,
partitioning strategy.
partitioning strategy
The policy used to determine the specic bucket for a eld in a partitioned table. SQLFire currently only supports
horizontal vs. vertical partitioning , so an entire row is stored in the same bucket. You can hash-partition a table
based on its primary key or on an internally-generated unique row id if the table has no primary key. Other
partitioning strategies can be specied in the PARTITION BY clause in a CREATE TABLE statement. The
strategies that are supported by SQLFire include hash-partitioning on columns other than the primary key,
range-partitioning , and list-partitioning.
peer client
Also known as the embedded client, this is a process that is connected to the distributed system using the GemFire
Peer Driver. The member may or may not host any data depending on the conguration property host-data. By
default, all peer clients will host data. Conguration describes how this property can be set at connection time.
Essentially, the peer client can be congured to just be a "pure" client or can be a client as well as a data store.
When hosting data, the member can be part of one or more server group.
peer driver
JDBC driver packaged in sqlfire.jar. The client connects to the distributed system using the SQLFire
driver using the URL jdbc:sqlfire: and doesn't specify a host and port in the URL. This driver provides
single-hop access to all the data managed in the distributed members. (The SQLFire JDBC thin-client driver
also supports one-hop access for lightweight client applications.)
query coordinator
The process that executes the query and determines the overall plan. It may distribute the query to the appropriate
fabric servers that host the data. When using a peer client , the query coordinator is the Peer Client itself. When
using a thin client, the query coordinator is the server member to which the client is connected.
range-partitioning
A partitioning strategy based on specied contiguous ranges of values of one or more elds. For example, a
table could be range-partitioned on a date eld such that all the values within a range of years are placed into
the same bucket.
vFabric SQLFire User's Guide722