This might help:
http://objectstyle.org/confluence/display/CAYDOC/Customizing+Queries
Borut Bolčina wrote:
Hi,
is this already implemented in some generic utility class?
-Borut
On 14.6.2005 23:03, Andrus Adamchik wrote:
No, SQLTemplate is actually used to run arbitrary SQL. In some cases the
result can be mapped to an entity, but in most it will be just that - a
list of Map objects with each Map corresponding to a result set data. So a
count query would look like this:
String sql = "SELECT COUNT(*) FROM SOME_TABLE"
DataMap queryRoot =
context.getEntityResolver().getDataMap("data_map_name");
SQLTemplate query = new SQLTemaplate(queryRoot, sql, true);
Map singleRow = (Map) context.performQuery(query).get(0);
Number count = (Number) singleRow.values().next();
As this is a bit too verbose, 1.2 will likely encapsulate this code in a
generic utility class. For now you can create your own.
Andrus
I read through that documentation, but it doesn't really appear to do
anything different then the normal SelectQuery besdies being able to
write it in SQL. I was wanting to do something like SELECT COUNT(*)
FROM Object and just got the int result, with out loading all the
child records etc.
Just reading the docs there it doesn't appear to let me do something like
that.
-Nick
On 6/14/05, Mike Kienenberger <[EMAIL PROTECTED]> wrote:
Nick Stuart <[EMAIL PROTECTED]> wrote:
This should be an easy one. I basically just want to find out how many
objects of a certain type there are. Easy to do with a SelectQuery and
user List.size() but does the cause any kind of performance issues?
Just thinking if these objects have child objects, which has more
child objects, will it pull all those when I Select the parent?
If you only want the count and don't want to load any objects, just use
SQLTemplate.
http://www.objectstyle.org/cayenne/userguide/fetch/sqltemplate.html
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