Have u solved the problem of like SQL? If yes then please share with me as i have not been able to solve it.
On Jun 11, 2:53 pm, RAVINDER MAAN <rsmaan...@gmail.com> wrote: > 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%2B > >> unsubscr...@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%2B > > unsubscr...@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. 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