Icon View Incident Report

Serious Serious
Reported By: Adam Commander
Reported On: 2/20/1999
For: Version 1.12 Build 1
# 315 Side-by-Side, or Star, Joins Are Not Working Properly in SQL SELECT Statements

Attached are two files:

Example1: Five table query that works
Example2: Five table query that AVs

The AV message is "Access Violation at address 0044707E read of address 00000100.

The two queries are identical, except that Example2 declares the order of the tables and joins randomly, while Example1 orders the tables and joins in their logical sequence (e.g. Customers to Orders, Orders, to Items, etc.). Interestingly, Example2 was generated by SRW, meaning that your query engine cannot always depend on the most logical ordering of tables, nor should SQL require this.

To replicate the problem, just create a directory with CUSTOMER, ORDERS, ITEMS, PARTS and VENDORS converted from the Delphi DBDEMOS directory to DBISAM.

Comments Comments
Problem was with doing side-by-side, or multi-way joins, in DBISAM. This problem would also be present when attempting a Cartesian join (no join condition).

Resolution Resolution
Fixed Problem on 2/27/1999 in version 1.13 build 1