According to RFC 4288 “Media Type Specifications and Registration Procedures”, type (eg. “application”) and subtype (eg “vnd…”) both can be max 127 characters. So including the slash, the maximum length is 255. Edit: Meanwhile, that document has been obsoleted by RFC 6838, which does not alter the maximum size but adds a remark: Also note … Read more
It’s still true. Even more than OO software, the database suffers if it isn’t treated precisely the way intended. And it wasn’t intended that you should interpose some abstraction layer in front of it. I think of impermeable abstraction layers as trying to build a Lego castle with all the pieces closed up into a … Read more
If you are using SQL Server Express, you won’t find a UI to run periodic backups. In this case you have to run a batch using Windows Scheduled Tasks or something similar. Don’t forget to use a user with enough privileges to access SQL Server. In the batch file “C:\Program Files\Microsoft SQL Server\100\Tools\Binn\SQLCMD.EXE” -S (local)\SQLExpress … Read more
Since it is unlikely that you have to retrieve the same 500 books every day: store the data retrieved from isbndb.com in a database and fill it up book by book.
Temporary tables are never WAL logged. Since they will be gone with the database session, there is never a need to recover them.
I have discussed this on the PostgreSQL mailing list (http://archives.postgresql.org/pgsql-bugs/2011-03/msg00041.php) and was informed on the reasoning for the behavior. Their answer is that “..you have to double quote relnames (listen “Test”). if you want the server not to case fold them. pg_notify takes a string, not a relname, which uses different rules.” (Thanks Merlin and … Read more
You can expand option 1 to have a 3rd column, giving a data-type. Your application can than use this data-type column to cast the value. But yeah, I would go with option 1, if config files are not an option. Another advantage of option 1 is you can read it into a Dictionary object (or … Read more
No, I don’t think an HTTP 502 Bad Gateway error is appropriate when a database error occurs. HTTP errors say something about the HTTP protocol. This specific error indicates a server is trying to relay the HTTP request, but the upstream server did not respond correctly. Your web application communicating with a database server is … Read more
By issuing rake -T you have the following database tasks: rake db:create # Create the database from DATABASE_URL or config/database.yml for the current Rails.env (use db:create:all to create all dbs in the config) rake db:drop # Drops the database using DATABASE_URL or the current Rails.env (use db:drop:all to drop all databases) rake db:fixtures:load # Load … Read more