Loading Only Certain Columns of a CSV File
lazarus / 16-Databases

----------------------------------------------------------------------
Jade · 2017-08-17 14:51

I am New to Lazarus and I have figured out how to load my CSV file
with the SdfDataSet but I can not figure out how to display only
certian parts of the CSV file. I only want to read in Col1, Col3, and
Col34 of my file into my Grid. I have tried with a DataBaseGrid and a
StringGrid. The DataGrid I have gotten to read just the first column
but the other ones i can not figure out. Any help would be
appreciated.

----------------------------------------------------------------------
Almir.Bispo · 2017-08-17 17:15

Hi ! I'm Lazarus and csv expert.
You can do like this:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
load(csvf,csvd:string);var s,d,res:tstringlist;       i:integer;begin
s:=tstringlist.create;d:=tstringlist.create;res:=tstringlist.create;d.
delimiter:=char(';'); //define delimiter used on
csvs.loadfromfile(csvf);//file (csv table) loadedfor i:= 0 to
s.count-1 dobegin d.delimitedtext:=s.strings[i]; //each row of file
(table)res.add(d.strings[0]);//define wich column by index number
"zero" is the first
columnend;res.savetofile(csvd); res.free;s.free;d.free; end;//how to u
se//load('c:\origenal.csv','c:\destin.csv');//sdf.active:=false;//sdf.
filename:='c:\destin.csv';//sdf.active:=true; 
But if do you want to work with csv like a true Database System,I
guess you know the NoSQL CSV Comp DB.
The solution is like this:
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i var
CQL:Stringlist;      Column:integer;begin
CQL:=Tstringlist.create;//what column to list?Column:= 0;//the first
colmun//CQL CommandCQL.add('{csv_table;@listar;0;0;0;0;query='+
inttostr(Column) +';destino=0}'); //save to imput os database
systemCQL.savetofile(application.location+'inpout_comp.exe');//execute
the csv parser database systemshellexecute(handle,pchar('open'),pchar(
application.location+'CSV_PARSER.exe'),nil,nil,0);//wait execution//it
depend on SO latencywhile not fileexiste('lock.inf') do begin {do
nothing} end;while  fileexiste('lock.inf') do begin {do nothing}
end;SDF.active:=false;SDF.filename:='csv_table.que'; //result
tableSDF.Active:=true;end; //The cql code is like:
Code: Javascript  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i {   
path\csv_table;    @listar;    0;    0;    0;    0;   
query=0;//define the Column here    destino=0} There are exemple with
Lazarus and NoSQL http://adltecnologia.blogspot.com.br

----------------------------------------------------------------------
Jade · 2017-09-06 16:24

thank you I actually finally got it to read i had the delimiter set to
; and my CSV file was separated by ,.
But any help on my new question i just posted would be appreciated.