Method and system for broadcasting and querying a database using a multi-function module

A multi-function database system module for broadcasting database tuples containing attribute information, for maintaining a local copy of such tuples, and for executing queries with respect to such tuples, said module comprising:

• a memory subsystem including means for receiving information from a source external to said module, storage means including a buffer memory and a storage memory for storing a local copy of such information, and means for broadcasting such information from said storage means both within the module and external to the module, and
• a processor for executing queries directed to such information in said memory system and for determining the function to be performed by the module in response to such queries and wherein
• said memory system further comprises
• first and second ports connected to said processor, said first and second ports for transferring attribute information to said processor, said second port also receiving said attribute information outputted from said processor,
• a third port for receiving externally broadcasted tuples and for transmitting tuples broadcasted from said memory subsystem, and
• loading logic for controlling the receipt of attribute information into said buffer memory in response to said processor, and wherein
• said storage memory is a first dual port memory connected to said second port and to said third port, for storing tuples and for broadcasting said stored tuples, and
• said buffer memory is a second dual port memory connected to said second port and to said third port, for receiving attribute information of said externally broadcasted tuples and said tuples broadcasted from said first dual port memory, and for transferring at least part of the received attribute information to said processors.

A broadcast database system module comprising:

• a processor for executing queries against attribute information of broadcasted tuples, and
• a memory subsystem for transferring said attribute information of said broadcasted tuples to said processor,
• said memory subsystem including means for decoupling the time intervals during which said tuples are broadcasted from the per tuple query execution time of said processor, and
• wherein said memory subsystem receives each of said broadcasted tuples in fixed length time intervals and transfers attribute information of said tuples to said processor in variable length time intervals, said variable length time intervals being on average less than or equal to said fixed length time intervals.

A broadcast database system comprising:

• a shared distribution medium, and
• a plurality of multi-function broadcast database system modules connected to said shared distribution medium, each of said multi-function broadcast database system modules comprising
• a processor, and
• a memory subsystem for transferring attribute information of broadcasted tuples to said processor, said memory subsystem including means for storing a copy of one or more of said broadcasted tuples and for cyclically broadcasting particular ones of the stored tuples, and
• wherein at least one of said broadcast database system modules is a pump module and at least one of said broadcast database system modules is a database mirror module, wherein said tuples broadcasted from said at least one pump module are received at said memory system of said at least one database mirror module and wherein said memory subsystem of said at least one database mirror module includes storing means for maintaining an up-to-date copy of the broadcasted tuples, said memory subsystem of said at least one base mirror module broadcasting said tuples of said copy if said at least one pump module fails.

A broadcast database system comprising:

• a shared distribution medium, and
• a plurality of multi-function broadcast database system modules connected to said shared distribution medium, each of said multi-function broadcast database system modules comprising
• a processor, and
• a memory subsystem for transferring attribute information of broadcasted tuples to said processor, said memory subsystem including means for storing a copy of one or more of said broadcasted tuples and for cyclically broadcasting particular ones of the stored tuples, and
• wherein at least one of said broadcast database system modules is a pump module and at least one of said broadcast database system modules is a data access manager module, wherein said tuples broadcasted from said at least one pump module are received at said one at least data access manager module, wherein said processor of said database access manager module executes queries against attribute information of said broadcasted tuples transferred from said memory subsystem of said database access manager module, and wherein the memory subsystem of said at least one data access manager module includes means for receiving and storing a snapshot of at least part of the tuples broadcasted thereto and means for locally broadcasting said snapshot within said memory system of said database access manager module.

A method of operating a multi-function database system module to execute queries, said module including a memory subsystem and a processor, said method comprising the steps of:

• using said processor, partitioning broadcasted tuples into sets by hashing a key attribute for each tuple,
• using said memory subsystem, transferring attribute information of said broadcasted tuples to said processor,
• using said processor, executing a query against attribute information of the partitioned broadcasted tuples, and
• using said processor, determining from said hashed key attribute value whether or not to execute a trigger procedure.

A method of operating a multi-function database system module to execute queries, said module including a memory subsystem and a processor, said method comprising the steps of:

• using said processor, partitioning broadcasted tuples into sets by hashing a key attribute for each tuple,
• using said memory subsystem, transferring attribute information of said broadcasted tuples to said processor, and
• using said processor, executing a query against attribute information of the partitioned, broadcasted tuples, and
• wherein said query is a join operation and said step of partitioning said tuples into sets by hashing occurs during a first pass, the method further comprising
• using said processor, selecting attribute information of said tuples partitioned and into said sets of a resultant joined relation during a second pass.