[appengine-java] Re: select count(*) ?
On 6 Paź, 10:03, "Jason (Google)" wrote: > * Because App Engine queries can only return up to 1,000 results, > count(this) will never return above 1,000, even if you have more than 1,000 > entities, so bear this in mind. I'm deeply shocked. This works like some black hole. You put your data there simply, but can't get them back that simply. In connection with restricions (inequality property filter), it is even harder to get anything more complex. BiGAppEngine disappointment. --~--~-~--~~~---~--~~ 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-java@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 -~--~~~~--~~--~--~---
[appengine-java] Re: select count(*) ?
The query restrictions are an artifact of the way App Engine's datastore is constructed, which makes certain operations (e.g. queries and reads) very fast and scalable but does limit the types of queries you can make, though you can typically get around these restrictions by re-thinking your model a bit. We are working on adding built-in cursor support for easier paging through entities and have just added a datastore statistics API for, among other things, getting the total entity count, even if it exceeds 1,000. More details here: http://code.google.com/appengine/docs/java/datastore/stats.html And we also have a data export utility included with the SDK to make it easier for you to back up or even move off of App Engine should you choose to, and we're continuing to look at ways of making App Engine, particularly the datastore component, easier to use. http://code.google.com/appengine/docs/python/tools/uploadingdata.html#Downloading_Data_from_App_Engine - Jason On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > * Because App Engine queries can only return up to 1,000 results, > > count(this) will never return above 1,000, even if you have more than > 1,000 > > entities, so bear this in mind. > > I'm deeply shocked. This works like some black hole. > > You put your data there simply, but can't get them back that simply. > > In connection with restricions (inequality property filter), it is > even harder to get anything more complex. > > BiGAppEngine disappointment. > > > > --~--~-~--~~~---~--~~ 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-java@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 -~--~~~~--~~--~--~---
[appengine-java] Re: select count(*) ?
Jason, the problem with the "increment a counter on your own" trick is that would be in a separate Transaction and thus, unreliably linked to the first insert Transaction right? Also, the Stats hook mentioned above is NOT realtime is it? I believe I read it is updated "at least once a day". On Oct 21, 12:54 pm, "Jason (Google)" wrote: > The query restrictions are an artifact of the way App Engine's datastore is > constructed, which makes certain operations (e.g. queries and reads) very > fast and scalable but does limit the types of queries you can make, though > you can typically get around these restrictions by re-thinking your model a > bit. > > We are working on adding built-in cursor support for easier paging through > entities and have just added a datastore statistics API for, among other > things, getting the total entity count, even if it exceeds 1,000. More > details here: > > http://code.google.com/appengine/docs/java/datastore/stats.html > > And we also have a data export utility included with the SDK to make it > easier for you to back up or even move off of App Engine should you choose > to, and we're continuing to look at ways of making App Engine, particularly > the datastore component, easier to use. > > http://code.google.com/appengine/docs/python/tools/uploadingdata.html... > > - Jason > > > > On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > > * Because App Engine queries can only return up to 1,000 results, > > > count(this) will never return above 1,000, even if you have more than > > 1,000 > > > entities, so bear this in mind. > > > I'm deeply shocked. This works like some black hole. > > > You put your data there simply, but can't get them back that simply. > > > In connection with restricions (inequality property filter), it is > > even harder to get anything more complex. > > > BiGAppEngine disappointment.- Hide quoted text - > > - Show quoted text - -- 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.
[appengine-java] Re: select count(*) ?
Jason, do you have a timeline for when: 1. the cursor feature will be available? 2. the data download feature be available for JAVA (not Python). On Oct 21, 10:54 am, "Jason (Google)" wrote: > The query restrictions are an artifact of the way App Engine's datastore is > constructed, which makes certain operations (e.g. queries and reads) very > fast and scalable but does limit the types of queries you can make, though > you can typically get around these restrictions by re-thinking your model a > bit. > > We are working on adding built-in cursor support for easier paging through > entities and have just added a datastore statistics API for, among other > things, getting the total entity count, even if it exceeds 1,000. More > details here: > > http://code.google.com/appengine/docs/java/datastore/stats.html > > And we also have a data export utility included with the SDK to make it > easier for you to back up or even move off of App Engine should you choose > to, and we're continuing to look at ways of making App Engine, particularly > the datastore component, easier to use. > > http://code.google.com/appengine/docs/python/tools/uploadingdata.html... > > - Jason > > > > On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > > * Because App Engine queries can only return up to 1,000 results, > > > count(this) will never return above 1,000, even if you have more than > > 1,000 > > > entities, so bear this in mind. > > > I'm deeply shocked. This works like some black hole. > > > You put your data there simply, but can't get them back that simply. > > > In connection with restricions (inequality property filter), it is > > even harder to get anything more complex. > > > BiGAppEngine disappointment. -- 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.
[appengine-java] Re: select count(*) ?
can anyone shine some lights on when the java datastore export will be available? On Dec 2, 11:19 am, king wrote: > Jason, do you have a timeline for when: > 1. the cursor feature will be available? > 2. the data download feature be available for JAVA (not Python). > > On Oct 21, 10:54 am, "Jason (Google)" wrote: > > > > > The query restrictions are an artifact of the way App Engine'sdatastoreis > > constructed, which makes certain operations (e.g. queries and reads) very > > fast and scalable but does limit the types of queries you can make, though > > you can typically get around these restrictions by re-thinking your model a > > bit. > > > We are working on adding built-in cursor support for easier paging through > > entities and have just added adatastorestatistics API for, among other > > things, getting the total entity count, even if it exceeds 1,000. More > > details here: > > >http://code.google.com/appengine/docs/java/datastore/stats.html > > > And we also have a dataexportutility included with the SDK to make it > > easier for you to back up or even move off of App Engine should you choose > > to, and we're continuing to look at ways of making App Engine, particularly > > thedatastorecomponent, easier to use. > > >http://code.google.com/appengine/docs/python/tools/uploadingdata.html... > > > - Jason > > > On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > > > * Because App Engine queries can only return up to 1,000 results, > > > > count(this) will never return above 1,000, even if you have more than > > > 1,000 > > > > entities, so bear this in mind. > > > > I'm deeply shocked. This works like some black hole. > > > > You put your data there simply, but can't get them back that simply. > > > > In connection with restricions (inequality property filter), it is > > > even harder to get anything more complex. > > > > BiGAppEngine disappointment. -- 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.
[appengine-java] Re: select count(*) ?
I second this question. Jorge Gonzalez On Dec 2, 1:19 pm, king wrote: > Jason, do you have a timeline for when: > 1. the cursor feature will be available? > 2. the data download feature be available for JAVA (not Python). > > On Oct 21, 10:54 am, "Jason (Google)" wrote: > > > The query restrictions are an artifact of the way App Engine's datastore is > > constructed, which makes certain operations (e.g. queries and reads) very > > fast and scalable but does limit the types of queries you can make, though > > you can typically get around these restrictions by re-thinking your model a > > bit. > > > We are working on adding built-in cursor support for easier paging through > > entities and have just added a datastore statistics API for, among other > > things, getting the total entity count, even if it exceeds 1,000. More > > details here: > > >http://code.google.com/appengine/docs/java/datastore/stats.html > > > And we also have a data export utility included with the SDK to make it > > easier for you to back up or even move off of App Engine should you choose > > to, and we're continuing to look at ways of making App Engine, particularly > > the datastore component, easier to use. > > >http://code.google.com/appengine/docs/python/tools/uploadingdata.html... > > > - Jason > > > On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > > > * Because App Engine queries can only return up to 1,000 results, > > > > count(this) will never return above 1,000, even if you have more than > > > 1,000 > > > > entities, so bear this in mind. > > > > I'm deeply shocked. This works like some black hole. > > > > You put your data there simply, but can't get them back that simply. > > > > In connection with restricions (inequality property filter), it is > > > even harder to get anything more complex. > > > > BiGAppEngine disappointment. -- 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.
[appengine-java] Re: select count(*) ?
just to follow up on a pending question back a few months ago. When the java datastore export will be available? On Dec 18 2009, 2:47 am, Jorge wrote: > I second this question. > > Jorge Gonzalez > > On Dec 2, 1:19 pm, king wrote: > > > > > Jason, do you have a timeline for when: > > 1. the cursor feature will be available? > > 2. the data download feature be available for JAVA (not Python). > > > On Oct 21, 10:54 am, "Jason (Google)" wrote: > > > > The query restrictions are an artifact of the way App Engine's datastore > > > is > > > constructed, which makes certain operations (e.g. queries and reads) very > > > fast and scalable but does limit the types of queries you can make, though > > > you can typically get around these restrictions by re-thinking your model > > > a > > > bit. > > > > We are working on adding built-in cursor support for easier paging through > > > entities and have just added a datastore statistics API for, among other > > > things, getting the total entity count, even if it exceeds 1,000. More > > > details here: > > > >http://code.google.com/appengine/docs/java/datastore/stats.html > > > > And we also have a data export utility included with the SDK to make it > > > easier for you to back up or even move off of App Engine should you choose > > > to, and we're continuing to look at ways of making App Engine, > > > particularly > > > the datastore component, easier to use. > > > >http://code.google.com/appengine/docs/python/tools/uploadingdata.html... > > > > - Jason > > > > On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > > > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > > > > * Because App Engine queries can only return up to 1,000 results, > > > > > count(this) will never return above 1,000, even if you have more than > > > > 1,000 > > > > > entities, so bear this in mind. > > > > > I'm deeply shocked. This works like some black hole. > > > > > You put your data there simply, but can't get them back that simply. > > > > > In connection with restricions (inequality property filter), it is > > > > even harder to get anything more complex. > > > > > BiGAppEngine disappointment. -- 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.
Re: [appengine-java] Re: select count(*) ?
Please check this out. You should be able to do queries returning greater than 1000 rows. Obviously we have to work with google bigtable constraints of 1000 rows etc. But our product does incremental queries to get you desired results. http://www.cloud2db.com On Thu, Dec 17, 2009 at 6:12 PM, king wrote: > can anyone shine some lights on when the java datastore export will be > available? > > On Dec 2, 11:19 am, king wrote: > > Jason, do you have a timeline for when: > > 1. the cursor feature will be available? > > 2. the data download feature be available for JAVA (not Python). > > > > On Oct 21, 10:54 am, "Jason (Google)" wrote: > > > > > > > > > The query restrictions are an artifact of the way App > Engine'sdatastoreis > > > constructed, which makes certain operations (e.g. queries and reads) > very > > > fast and scalable but does limit the types of queries you can make, > though > > > you can typically get around these restrictions by re-thinking your > model a > > > bit. > > > > > We are working on adding built-in cursor support for easier paging > through > > > entities and have just added adatastorestatistics API for, among other > > > things, getting the total entity count, even if it exceeds 1,000. More > > > details here: > > > > >http://code.google.com/appengine/docs/java/datastore/stats.html > > > > > And we also have a dataexportutility included with the SDK to make it > > > easier for you to back up or even move off of App Engine should you > choose > > > to, and we're continuing to look at ways of making App Engine, > particularly > > > thedatastorecomponent, easier to use. > > > > >http://code.google.com/appengine/docs/python/tools/uploadingdata.html. > .. > > > > > - Jason > > > > > On Mon, Oct 19, 2009 at 1:53 PM, vetch wrote: > > > > > > On 6 Paź, 10:03, "Jason (Google)" wrote: > > > > > * Because App Engine queries can only return up to 1,000 results, > > > > > count(this) will never return above 1,000, even if you have more > than > > > > 1,000 > > > > > entities, so bear this in mind. > > > > > > I'm deeply shocked. This works like some black hole. > > > > > > You put your data there simply, but can't get them back that simply. > > > > > > In connection with restricions (inequality property filter), it is > > > > even harder to get anything more complex. > > > > > > BiGAppEngine disappointment. > > -- > > 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. For more options, visit this group at http://groups.google.com/group/google-appengine-java?hl=en.
