Re: [web2py] Re: Large datasets

2010-01-21 Thread Johann Spies
2010/1/15 mr.freeze : > WebGrid can handle large datasets as it limits the query by the page > size if the datasource is a Set or Table(s).  The performance hit will > come in when the filter row is enabled since each filter is a query > for all distinct values in a field. I would try disabling the

[web2py] Re: Large datasets

2010-01-15 Thread mdipierro
This is ok for small datasets. No way to make it scale. I would use some tricks using ListPropery. On GAE really everything depends on details. On Jan 15, 3:34 am, toan75 wrote: > Thank mdipierro. > But i want use "find" on GAE: >         rows = db(db.cat.id>0).select() >         rows = rows.find

[web2py] Re: Large datasets

2010-01-15 Thread toan75
Thank mdipierro. But i want use "find" on GAE: rows = db(db.cat.id>0).select() rows = rows.find(lambda row:row.name.startswith("C"))) rows = rows.sort(lambda row:row.name) rows = rows[1:10] replace this code on RDBS: rows = db(db.cat.name.like("C%")).select (orderby

[web2py] Re: Large datasets

2010-01-14 Thread mdipierro
This rows = db(db.cat.id>0).select(orderby=db.cat.name,limitby=(1,10)) works on GAE and it is fast. mind that you should start counting at 0, not 1. On Jan 15, 12:44 am, toan75 wrote: > On RDBS, i have code: >         rows = db(db.cat.id>0).select(orderby=db.cat.name,limitby=(1,10)) > but on G

[web2py] Re: Large datasets

2010-01-14 Thread toan75
On RDBS, i have code: rows = db(db.cat.id>0).select(orderby=db.cat.name,limitby=(1,10)) but on GAE: rows = db(db.cat.id>0).select() rows = rows.sort(lambda row:row.name) rows = rows[1:10] It spend long time in a large datasets. Is there some other way i can use to ma

[web2py] Re: Large datasets

2010-01-14 Thread mr.freeze
WebGrid can handle large datasets as it limits the query by the page size if the datasource is a Set or Table(s). The performance hit will come in when the filter row is enabled since each filter is a query for all distinct values in a field. I would try disabling the filter row with: grid.enable

[web2py] Re: Large datasets

2010-01-14 Thread mdipierro
The web2py DAL sipmly provides an interface to your database. There is no overhead that depends on the size of your dataset. If you database can handle it, web2py can. There are exceptions. For example the requires=IS_IN_DB(..,) validator builds an in-memory list of all the references in order to