Method for processing a data base

• US 4,644,471 A
• Filed: 12/21/1984
• Issued: 02/17/1987
• Est. Priority Date: 12/23/1983
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kojima, Keiji, Torii, Shunichi
• Primary Examiner(s): Zache, Raulfe B.
• Application Number:
  US06/684,789
• Time in Patent Office: 788 Days
• Field of Search: 364/300
• US Class Current: 1/1
• CPC Class Codes: G06F 16/284 Relational databases
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching

Abstract

The data elements for a column of a table are fetched from irregular address locations in memory and stored as vector data with a regular address increment. Vector designating data is also generated which includes at least the first element address of the stored vector data and the increment of the vector. The vector data is processed by a program routine which can perform the processing required by a selected command and which includes vector instructions each designating at least one set of vector data elements to be executed, in such a manner that vector data elements are fetched successively from the data storage device and are supplied successively to a pipelined arithmetic or logical operation unit.

Claims

1. A method for processing a data base in a computer, which data base comprises a plurality of data tables to be processed, each comprised of a plurality of columns and rows, a plurality of data elements belonging to respective rows of the same column being assigned storage locations within a data storage device whose addresses are not uniformly separated from those for respective data elements in the neighboring rows, the method comprising the steps of:

generating a command requesting processing of data elements belonging to selected columns within selected tables;

accessing the data elements within the storage device which belong to the selected columns within the selected tables, in response to said command, to fetch and store the accessed data elements so that data elements belonging to each selected columns within each selected table are stored as vector data at locations within said storage device whose addresses are separated by a uniform increment from those for respective rows in the selected table;

storing vector designating data for each vector data including at least the first element address and an address increment for each vector data;

executing a program routine which can perform the processing requested by the command, and which includes vector instructions each designaing at least one vector data to be executed and the kind of processing to be carried out, said program routine being executed in such a manner that elements of vector data designated by a vector instruction are successively accessed, based upon the vector designating data for the designated vector data and are sent from the storage device to a piplelined arithmetic or logical operation unit in order to effect operation thereon successively.

2. A method according to claim 1, wherein a plurality of data elements belonging to respective rows and to the same column of a selected data table are assigned storage loations within the data storage device whose addresses are defined by a combination of a data page number and a slot number, said data page number designating the start addresses of a corrsponding one of data pages in which the storage locations of the data storage device are divided, and said slot number designating an address of a corresponding one of a plurality of slot pointers in which an address of a storage location on the page for a corresponding data element is stored, wherein said step of accessing data elements belonging to a selecteed column with a selected table includes:

accessing the slot pointers for data elements within the selected column within the selected table, based upon the data page number and the slot number, in order to fetch addresses for the data elements to store the fetched addresses as a list vector data in said data storage device;

accessing data elements for stored list vector data; and

accessing said data storage device, based upon said accessed list vector data, to fetch said data elements from said data storage device successively.

3. A method according to claim 1, wherein said program routine includes a joint routine for finding first data elements from a first vector data each belonging to a selected column of a first selected table and at the same time belonging to a first selected column of a second selected table, and finding second data elements from a second vector data each belonging to a second selected column within the first table and belonging to the same row within the first selected table as one of the first data elements, and finding third data elements from a third vector data each belonging to a second selected column within the second selected table and to the same row within the second selected row as one of the first data elements.