ohhhhh thank you!!! will test asap, thanks so much
在 2016年5月26日星期四 UTC+8下午1:17:40，Jacob Quinn写道： > > Yep, > > like I said, just switch your "using" statements around to make sure > "using DataFrames" comes before "using SQLite" > > -Jacob > > On Wed, May 25, 2016 at 11:15 PM, SHORE SHEN <[email protected] > <javascript:>> wrote: > >> Hi: >> >> heres my codes: >> >> using SQLite >> using DataFrames >> >> db=SQLite.DB("test3.db") >> query(db,"create table emp (id integer, name text)") >> query(db,"insert into emp (id, name) values(1,'jay')") >> query(db,"insert into emp (id, name) values(2,'kay')") >> query(db,"insert into emp (id, name) values(4,'vay')") >> >> y=SQLite.query(db,"select * from emp") >> z=Data.stream!(SQLite.Source(db,"select * from emp"), Data.Table) >> >> DataFrame(z) >> >> and the error reported: >> >> MethodError: `convert` has no method matching >> convert(::Type{DataFrames.DataFrame}, >> ::DataStreams.Data.Table{Array{NullableArrays.NullableArray{T,1},1}}) >> This may have arisen from a call to the constructor >> DataFrames.DataFrame(...), >> since type constructors fall back to convert methods.WARNING: Error >> showing method candidates, aborted >> >> in call at essentials.jl:56 >> in include_string at C:\Users\shoren\.julia\v0.4\CodeTools\src\eval.jl:28 >> in include_string at C:\Users\shoren\.julia\v0.4\CodeTools\src\eval.jl:32 >> [inlined code] from C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:39 >> in anonymous at C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:62 >> in withpath at C:\Users\shoren\.julia\v0.4\Requires\src\require.jl:37 >> in withpath at C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:53 >> [inlined code] from C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:61 >> in anonymous at task.jl:58 >> >> 在 2016年5月26日星期四 UTC+8下午12:45:00，Jacob Quinn写道： >>> >>> Make sure you do >>> >>> using DataFrames >>> using SQLite >>> >>> in that order in a fresh Julia session to ensure the conversion methods >>> get defined (when you load the SQLite package, it checks if DataFrames has >>> already been loaded to define the conversion routines). >>> >>> -Jacob >>> >>> >>> On Wed, May 25, 2016 at 10:43 PM, SHORE SHEN <[email protected]> >>> wrote: >>> >>>> Hi Alex >>>> >>>> thanks so much for your reply, I tried out the method but it fails when >>>> using DataFrame(Data.stream!(source, Data.Table)) commend. It reported >>>> no such method error msg as follow: >>>> >>>> MethodError: `convert` has no method matching >>>> convert(::Type{DataFrames.DataFrame}, >>>> ::DataStreams.Data.Table{Array{NullableArrays.NullableArray{T,1},1}}) >>>> This may have arisen from a call to the constructor >>>> DataFrames.DataFrame(...), >>>> since type constructors fall back to convert methods.WARNING: Error >>>> showing method candidates, aborted >>>> >>>> in call at essentials.jl:56 >>>> in include_string at >>>> C:\Users\shoren\.julia\v0.4\CodeTools\src\eval.jl:28 >>>> in include_string at >>>> C:\Users\shoren\.julia\v0.4\CodeTools\src\eval.jl:32 >>>> [inlined code] from C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:39 >>>> in anonymous at C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:62 >>>> in withpath at C:\Users\shoren\.julia\v0.4\Requires\src\require.jl:37 >>>> in withpath at C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:53 >>>> [inlined code] from C:\Users\shoren\.julia\v0.4\Atom\src\eval.jl:61 >>>> in anonymous at task.jl:58 >>>> >>>> 在 2016年5月26日星期四 UTC+8上午12:30:52，Alex Mellnik写道： >>>> >>>>> >>>>> Yes to both! >>>>> >>>>> For the first one, you want to use Data.stream! to get a Data.Table >>>>> from the result set, and then convert it to a DataFrame. For the second >>>>> you need to do the opposite. I generally work with DataFrames so I wrote >>>>> two convenience functions for doing this, which should give you an idea >>>>> of >>>>> how to go about it: >>>>> >>>>> function queryToDF(db, query) >>>>> source = SQLite.Source(db, query) >>>>> return DataFrame(Data.stream!(source, Data.Table)) >>>>> end >>>>> >>>>> function dfToDB(db, df, table) >>>>> sink = SQLite.Sink(Data.Table(df), db, table) >>>>> Data.stream!(Data.Table(df), sink) >>>>> end >>>>> >>>>> Cheers -A >>>>> >>>>> On Wednesday, May 25, 2016 at 2:54:26 AM UTC-7, SHORE SHEN wrote: >>>>>> >>>>>> Hello >>>>>> >>>>>> Im trying out the sqlite package in julia, I got the following 2 >>>>>> questions: >>>>>> >>>>>> 1, the query will result in a type of SQLite.ResultSet, if i can >>>>>> output dataframe or dataarry type? >>>>>> >>>>>> 2, if i have a dataframe or dataarray type, would i be able to put it >>>>>> into the database table? >>>>>> >>>>>> thanks a lot! >>>>>> >>>>> >>> >
