number of employee entities is going to be high .So i guess that possibility of getting more then 1000 employees for any search is quite high.
On Fri, Jun 11, 2010 at 6:56 PM, John Patterson <jdpatter...@gmail.com>wrote: > A lot depends on how many Employee entities you have. > > You could do a sub search for each of the 4 employee types and use COUNT to > get the results. This will only work up to 1000 employees per employee > type. > > Twig can execute queries in parallel so this would take no more time than > running your original query. > > On 11 Jun 2010, at 19:39, RAVINDER MAAN wrote: > > Thanks for your reply Ravi > let me explain the entire scenario.I have an employee entity .User can > search employees by giving part of name .There are four type of employees .I > have to show number of employees matching user search criteria for every > type of employee under different tabs.Actual results are to be displayed > only if user open that tab. > In SQL term we could write following query > > Select count(*) from employee where name like '%<searchname>%' and type > ='A' ; > > My first problem is that i dint find any equivalent of like operator.Is > there any way to do it? > Secondly we can not keep record count for each search combination.what will > you suggest for this case? > Thanks once again. > > > > > On Fri, Jun 11, 2010 at 4:23 PM, Ravi <ping2r...@gmail.com> wrote: > >> Google app engine designed to work for any numbers of records with in >> minimum time, so SQL features like counting the records whenever >> needed is not supported. >> So you need to take care of such counter by urself at the time of >> adding or deleting the records in a table/entity. >> >> If you just want total number of records and dont care if counting >> happened in last 24 hours then look into low level api for datastore >> statistics, GAE refreshes total count every 24 hours and you can read >> the total count from there. >> >> And if you want count of records with some where clause, then you need >> to maintain it. >> >> like if u want like this >> select count(0) from tb where tb.propA='someValue' >> >> then you may need to create a new entity say counterForTb, and have >> few fields entityName and count and where clause columns >> and whenevr you add a new record in tb then increase the count of that >> record in counter table and on delete decrease it. >> >> >> >> >> Something for google guys >> Just realized that all columns are indexed unless we specify to not to >> index, and there must be some index meta data/statistics saved >> somewhere in google data stores about index(like total records >> matching to this index). And if that stats can be accessible through >> some APIs then we may be able to get total count just by reading data >> from indexes stats. >> Is this something feasible? >> >> >> >> >> >> >> >> >> On Jun 11, 11:39 am, RAVINDER MAAN <rsmaan...@gmail.com> wrote: >> > How can we get records count for a query in JDO. >> > In sql we have select count(*) from <table_name> >> > i want to get number of records returned by a query. what is the >> > efficient way to do that.One option is to use size() function .I think >> > it is not best way. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Google App Engine for Java" group. >> To post to this group, send email to >> google-appengine-j...@googlegroups.com. >> To unsubscribe from this group, send email to >> google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> >> . >> For more options, visit this group at >> http://groups.google.com/group/google-appengine-java?hl=en. >> >> > > > -- > Regards, > Ravinder Singh Maan > > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To post to this group, send email to > google-appengine-j...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine for Java" group. > To post to this group, send email to > google-appengine-j...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine-java+unsubscr...@googlegroups.com<google-appengine-java%2bunsubscr...@googlegroups.com> > . > For more options, visit this group at > http://groups.google.com/group/google-appengine-java?hl=en. > -- Regards, Ravinder Singh Maan -- You received this message because you are subscribed to the Google Groups "Google App Engine for Java" group. To post to this group, send email to google-appengine-j...@googlegroups.com. To unsubscribe from this group, send email to google-appengine-java+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
