Hi Brian,
Specifying "upgrade=true" on an already upgraded database should be
harmless. Here's how to determine if the database needs to be upgraded:
1) The database needs to be upgraded if the (two digit) on-disk version
of the database is less than the leading two digits of the Derby release
identifier.
2) The on-disk version of the database can be obtained by the following
query. Note this is not part of Derby's public API and so could change
in the future. However, this part of the API has remained stable for the
last 4 years:
values ( syscs_util.syscs_get_database_property(
'DataDictionaryVersion' ) )
3) The release identifier can be obtained via sysinfo.
Hope this helps,
-Rick
[EMAIL PROTECTED] wrote:
How do I tell if the database needs to be upgraded? Or is there no
impact if I specify "upgrade" but one is not necessary?
Brian
On Mon, Dec 8, 2008 at 8:43 AM, Rick Hillegas wrote:
Brian Peterson wrote:
I'm trying to figure out how to determine what connection parameters
for an
embedded database I should use when there might not be a database in
place
(so "create=true"), or there might be an older version already in
place (so
"upgrade=true"), or there might already be a database of the right
version
in place (so "create" or add nothing to the URL).
I read that "upgrade" and "create" cannot both be specified in the
connection URL. If I'm putting out a release of my application that
uses the
latest version of Derby (10.4) while a previous version used 10.2.2,
what
are the recommended steps for making the connection to the Derby
database if
one is already present? (Note that I have to handle this
programmatically as
part of the application startup.)
Do I first try a URL with "create" and see if there's an error, and
if so,
follow up with a call with "upgrade"? Or do I have the procedure
always use
"upgrade" and follow up with a URL with "create" if it fail to make a
Hi Brian,
Your first approach sounds good to me:
1) Bring up the database, specifying "create=true"
2) If you get the warning that the database already exists, then
bring down the database and reboot it in upgrade mode
Regards,
-Rick
connection?
Brian
