Bug #27849 | version incompatibility for comma operator between 4.1.x and 5.0.x | ||
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Submitted: | 16 Apr 2007 12:21 | Modified: | 18 Apr 2007 7:07 |
Reporter: | Vadim Smelyansky | Email Updates: | |
Status: | Verified | Impact on me: | |
Category: | MySQL Server: General | Severity: | S4 (Feature request) |
Version: | 5.0.37 | OS: | Linux |
Assigned to: | CPU Architecture: | Any | |
Tags: | incompatibility |
[16 Apr 2007 12:21]
Vadim Smelyansky
[16 Apr 2007 12:40]
Valeriy Kravchuk
Thank you for taking the time to write to us, but this is not a bug. Please double-check the documentation available at http://dev.mysql.com/doc/refman/5.0/en/join.html: "Previously, the comma operator (,) and JOIN both had the same precedence, so the join expression t1, t2 JOIN t3 was interpreted as ((t1, t2) JOIN t3). Now JOIN has higher precedence, so the expression is interpreted as (t1, (t2 JOIN t3)). This change affects statements that use an ON clause, because that clause can refer only to columns in the operands of the join, and the change in precedence changes interpretation of what those operands are. ..."
[17 Apr 2007 20:07]
Vadim Smelyansky
It is not a bug in code it is usability and backward compatibility bug You can not just broke applications just because there is a new version of MySQL There should be at least option in config file to keep it compatible (like old_passwords for example) may be old_join
[18 Apr 2007 7:07]
Valeriy Kravchuk
I agree that some backward compatibility mode for JOINs will be very useful. So, this is a reasonable feature request, but, formally, not a bug.