Need Help On Best Querying ( is LINQ work with Huge amount of data..)

[ranganadh]

Dear Group members,


I am new to LINQ, pls help on the deeling with huge amount of data
with the C# stand Alone application.

I have two file, which contains more then 2 lacs lines in every file

suppose file1 like ...

999361894 422021100257001
899119011 422021100344217
899373022 422021100262179
892044443 422021100426945
899292491 422021000154860
----
----

and file2 looks like

92000000,422021100420675
92000002,422021100420403
92000003,422021100420614
92000004,422021100425785
92000005,422021100422232
---
----

values under each file divided by different set of delimiter, and this
delimiter can be changed... ie some files came with some other
delimiter with more fields also.

My motive is to import different kind of formated files to my
application, and generate some auto-summarized report like ... 99999
is missed in file 2, and 99999 no is missed in file 1, and for this
id 999999, values are not matching ..



for this thing, i succeeded agenest the import various typed files to
my data grid.


Remain-thing, major thing is compare the files and generate summary
report, kindly remember i don't have Database support for my
application, and all data came with different formates and data will
be came like text files.

So, that i am starting with small comparison with LINQ,


like
DataTable dt1;//hold's the first file data
DataTable dt2; // hold's the second file data.

When i try to find out the records which are having dt1 and not in
dt2. with LINQ

var test= from k in dt1.AsEnumerable() where !(from t in
dt2.AsEnumerable() select
Field<string>(0)).Contains(k.Field<string>(0)) select k;

myResult_DataGrid.Datasource = test.AsDataView();


These steps running from server from mints, still application is look
like executing same statment.

i don't know what is the cause of hangout the application, it's look
like a problem with the huge amount of data, ofcource it nearly
having 2lac's X 2 lacs

is there any other solutions, to do this type of thigs? is there any
problem in my LINQ statement?

pls let me know , if anybody having the solutions on this type of
programs.


Thanks and Regards
ranganadh Kodali

 

[Jon Skeet [C# MVP]]

So, that i am starting with small comparison with LINQ,


like
DataTable dt1;//hold's the first file data
DataTable dt2; // hold's the second file data.

Any reason for using DataTables to start with? Why not just load the
data into strongly typed objects yourself?

When i try to find out the records which are having dt1 and not in
dt2. with LINQ

var test= from k in dt1.AsEnumerable() where !(from t in
dt2.AsEnumerable() select
Field<string>(0)).Contains(k.Field<string>(0)) select k;

That will indeed take a long time. If you want to find elements which
are in the first sequence but not not in the second, use the Except()
method.

That will quite possibly be easier if you use your own objects rather
than DataTables.