aku-aku: v.. To move a tall, flat bottomed object (such as a bookshelf) by swiveling it alternatively on its corners in a "walking" fashion. [After the book by Thor Heyerdahl theorising the statues of Easter Island were moved in this fashion.] source: LangMaker.com. Aku Aku also has another meaning to the islanders: a spiritual guide.
« Upgrading to Rails 2.x from 1.2.6 | Main Page | 32 of 52: Camp Tipsy »
weird mysql date issues
Posted by dav at 2008 April 30 10:51 AM
File under:

We got a new Continuous Integration box from Pivotal Labs yesterday and I ran into some weird MySQL time based issues when trying to get our tests to pass on it. It turned out that the CI box was running MySQL v 3.0.38, but all of our dev boxen were running v 3.0.45. Here's some difference between these two versions:

v.45 will happily take a clause of the format SELECT * FROM a_table WHERE end_date < '07-12-31' while v.38 isn't so happy with it. In this case, I have to hand it to v.38, because that date was in YY-MM-DD format which is about the most retarded date format I've seen in production code. I changed the Date#to_mysql method to use YYYY-MM-DD format and all was well.

The second issue was more odd. In v.45 if you compare a date column value with a time, the date is treated as a time value set to 00:00:00 of the day for the comparison. In other words, if the value in the date column is 2006-07-05 and you compare that with '2006-07-05 00:00:00' they are equal. Not so in v.38:

mysql> create table delme ( a date );
Query OK, 0 rows affected (0.03 sec)
mysql> insert into delme (a) values ('2006-07-05');
Query OK, 1 row affected (0.01 sec)
mysql> select * from delme where a < '2006-07-05';
Empty set (0.00 sec)
mysql> select * from delme where a < '2006-07-05 00:00:00';
| a          |
| 2006-07-05 |
1 row in set (0.00 sec)
I found out that the production box is running v3.0.51 so we've now upgraded all of our workstations and deployment/testing machines to that.

Post a new comment:

Thanks for signing in, . Now you can comment. (sign out)

(If you haven't left a comment here before, you may need to be approved by the site owner before your comment will appear. Until then, it won't appear on the entry. Thanks for waiting.)

Remember me?