The entity-relationship model—toward a unified view of data
ACM Transactions on Database Systems (TODS) - Special issue: papers from the international conference on very large data bases: September 22–24, 1975, Framingham, MA
System R: relational approach to database management
ACM Transactions on Database Systems (TODS)
Ethernet: distributed packet switching for local computer networks
Communications of the ACM
The cedar DBMS: a preliminary report
SIGMOD '81 Proceedings of the 1981 ACM SIGMOD international conference on Management of data
On extending the functions of a relational database system
SIGMOD '82 Proceedings of the 1982 ACM SIGMOD international conference on Management of data
A processor for a high-performance personal computer
ISCA '80 Proceedings of the 7th annual symposium on Computer Architecture
ICSE '84 Proceedings of the 7th international conference on Software engineering
A CODASYL CAD data base system
DAC '81 Proceedings of the 18th Design Automation Conference
The relational/network Hybrid data model for Design Automation Databases
DAC '81 Proceedings of the 18th Design Automation Conference
System facilities for CAD databases
DAC '80 Proceedings of the 17th Design Automation Conference
Weaknesses of commercial data base management systems in engineering applications
DAC '80 Proceedings of the 17th Design Automation Conference
A database approach for managing VLSI design data
DAC '82 Proceedings of the 19th Design Automation Conference
SIGMOD '87 Proceedings of the 1987 ACM SIGMOD international conference on Management of data
Mathemtical Model of Composite Objects and Its Application for Organizing Engineering Databases
IEEE Transactions on Software Engineering
An Extended Relational Database System and It's Application to Management of Logic Diagrama
VLDB '86 Proceedings of the 12th International Conference on Very Large Data Bases
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Databases have a number of advantages over specialized design files for use in the VLSI design process. Balanced against these advantages is the presumed extra run-time cost of accessing the database. In particular, ordinary relational databases appear to be too slow to be used on-line by engineers in the design process [Eastman 80, Haynie 81, Sidle 80, Stonebraker 82].The requirements for design access include the retrieval of major units of data at one time, implying joins of many attributes with their libraries, and projections to obtain the relevant attributes for a given study. Previously, in order to test if databases could achieve acceptable performance at all, we experimented using a CODASYL database system [Beetem 82, Wiederhold 82]. This appeared to provide adequate performance, but at a high cost of software maintenance and lack of flexibility due to CODASYL limitations.Our hypothesis is that the relational data model per se is not the crucial factor in performance; rather, the internal access mechanisms of the database significantly affect performance. To test this hypothesis, we ran experiments using the Cypress database system in the Cedar environment at Xerox Palo Alto Research Center. The program used is a design macro expander, more fully described in Section 3. The tests show that collocating pointers to all relations that a VLSI component appears in will reduce CPU time spent in the main database access routines by 25%.We repeated a subset of these experiments on a Digital VAX 750 using the Structured Design System (SDS) of Silvar-Lisco [SL 83] with specialized design files rather than a database management system, and found that when a structured result file is used, the largest component of execution time is the time spent writing out the expansion results.