gi7mhl
asked on
CSV files
is it possible to use sql to delete records from a csv database. if not what alternative can i use to modify my csv database (alter field values, delete records).
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DragonSlayer
or use this http://jansfreeware.com/jvcsvbase.zip
Or use Delphi to read the comma-delimited file, put the records in a TGrid of some kind, add/delete/modify records, and write the CSV file back...
this is the Delphi section, after all :D
this is the Delphi section, after all :D
You can create a custom dataset using whatever underlying file type you like. You can either use the BDE or ADO to connect to it.
FrankTheRat
FrankTheRat
Hello!
A CSV file has comma separated values.
To get the column values of each row, you could use the commatext property of a TStrings.
example code
MyCSVProc(FlNm: String);
Var
MyCSVFL, MyCSVRow: TStringList;
FilRecCtr, FilColCtr: Integer;
Begin
Try
begin
MyCSVFl := TStringList.Create;
MyCSVFl.LoadFromFile(FlNm)
MyCSVRow := TSTringList.Create;
//This if for the rows
For FilRecCtr := 0 to MyCSVFl.Count -1 Do
Begin
//read record
MyCSVRow.CommaText := MyCSVFL[FilRecCtr];
(* if you are using a StringGrid *)
//stringGrid1.Rows[FilRecC
//This if for the columns
FOr FilColCtr := 0 to MyCSVRow.Count -1 Do
Begin
//Code your modification logic here.
MyCSVRow[FilColCtr] := MyCSVRow[FilColCtr];
End;
//write modified record
MyCSVFL[FilRecCtr] := MyCSVRow.CommaText;
End;
MyCSVFl.SaveToFile(FlNm);/
end
except on e: exception do
ShowMessage(e.Message);
end;
End;
...Snehanshu
"When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That's relativity."
A CSV file has comma separated values.
To get the column values of each row, you could use the commatext property of a TStrings.
example code
MyCSVProc(FlNm: String);
Var
MyCSVFL, MyCSVRow: TStringList;
FilRecCtr, FilColCtr: Integer;
Begin
Try
begin
MyCSVFl := TStringList.Create;
MyCSVFl.LoadFromFile(FlNm)
MyCSVRow := TSTringList.Create;
//This if for the rows
For FilRecCtr := 0 to MyCSVFl.Count -1 Do
Begin
//read record
MyCSVRow.CommaText := MyCSVFL[FilRecCtr];
(* if you are using a StringGrid *)
//stringGrid1.Rows[FilRecC
//This if for the columns
FOr FilColCtr := 0 to MyCSVRow.Count -1 Do
Begin
//Code your modification logic here.
MyCSVRow[FilColCtr] := MyCSVRow[FilColCtr];
End;
//write modified record
MyCSVFL[FilRecCtr] := MyCSVRow.CommaText;
End;
MyCSVFl.SaveToFile(FlNm);/
end
except on e: exception do
ShowMessage(e.Message);
end;
End;
...Snehanshu
"When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That's relativity."
It seems that the ttASCII table type of Delphi's TTable does not support CSV as documented.
I found a freeware component that lets you use a csv file as a table (hopefully supporting queries et al).
You could Download and install:
http://www.leif-bruder.de/download/LbCsv.zip
I could view the csv file in a DBGrid using this component and a dataset.
...Snehanshu
I found a freeware component that lets you use a csv file as a table (hopefully supporting queries et al).
You could Download and install:
http://www.leif-bruder.de/download/LbCsv.zip
I could view the csv file in a DBGrid using this component and a dataset.
...Snehanshu
Why don't you extend the Demos/db/textdata example to support CSV files instead of working on a line-per-line basis ?
I really doub't you'll find a CSV TDataSet descendant with an SQL parser and optimizer engine that will support queries.
A more simple approach would be for you to use a some sort of TMemoryTable and load the CSV file to it. That will enable all dbaware controls and all you'll have to do is manually load and save the contents of the memory stream to your csv file (which should be quite simple).
An example of an open-source / freeware TMemoryTable can be found in RXLib.
I really doub't you'll find a CSV TDataSet descendant with an SQL parser and optimizer engine that will support queries.
A more simple approach would be for you to use a some sort of TMemoryTable and load the CSV file to it. That will enable all dbaware controls and all you'll have to do is manually load and save the contents of the memory stream to your csv file (which should be quite simple).
An example of an open-source / freeware TMemoryTable can be found in RXLib.