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Table Of Contents
The SQLFire community site provides a comparison of SQLFire to other data management systems, such as
vFabric GemFire.
Apache Derby RDBMS Components
SQLFire integrates vFabric GemFire functionality with several components of the Apache Derby relational
database management system (RDBMS):
JDBC driver. SQLFire supports a native, high performant JDBC driver (peer driver) and a thin JDBC driver.
The peer driver is based on the Derby embedded driver and JDBC 4.0 interfaces, but all communication with
SQLFire servers is implemented through the vFabric GemFire distribution layer.
Query engine. SQLFire uses Derby to parse the SQL queries and generate parse trees. SQLFire injects its own
logic for intermediate plan creation and distributes the plan to data stores in the cluster. SQLFire also capitalizes
on some aspects of the built-in optimizer in Derby to generate query plans. The query execution itself uses
memory-based indexes and custom storage data structures. When query execution requires distribution, SQLFire
uses a custom algorithm to execute the query in parallel on multiple data stores.
Network server. SQLFire servers embed the Derby network server for connectivity from thin JDBC and
ADO.NET clients. The communication protocol is based on the DRDA standard that is used by in IBM DB2
drivers.
SQL Extensions
vFabric SQLFire modies and extends the query engine and SQL interface to provide support for partitioned
and replicated tables, data-aware procedures, data persistence, data eviction, and other features unique to the
distributed SQLFire architecture. SQLFire also adds SQL commands, stored procedures, system tables, and
functions to help easily manage features of the distributed system, such as persistent disk stores, listeners, and
locators.
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Overview of vFabric SQLFire