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Using FastDBF I am creating DBF files on the fly dynamically) with data fed through text files. The problem is that there is always one blank column at the very end of the file. This is always true. I want to just be able to remove the very last column, and my code does this, however it seems to shift all of the data in the file arouns and turns it into a mess. In terms of code, I am just simply using these line before I close the file
odbf.Header.Unlock();
odbf.Header.RemoveColumn(colCount - 1);
It requires you to unlock to make this edit, and colCount is just the number of columns the file has. It does successfully remove the last column, but like I said it shifts all of the data round with it.
Need to insert a local .csv file, around 6MB, 130k rows. I need to open the file in a c# program, insert each row, each row having special considerations (quotes around each field).
Wondering the best way to go about this, as I've never written a c# app the inserts to a db. I have done the below directly on the DB, but now need to do this within a c# app.
BULK
INSERT CSVTest
FROM 'c:\csvtest.txt'
WITH
(
FIELDTERMINATOR = ',',
ROWTERMINATOR = '\n'
)
GO
The sample data within the .csv file is below, and I'm a little lost on how to strip the quotes out when inserting to the DB from c#. Do I need to specify the column names in c#, or can I insert something similar to the T-SQL query?
Copyright (c) 2011 MaxMind Inc. All Rights Reserved.
"beginIp","endIp","beginIpNum","endIpNum","countryCode","countryName"
"1.0.0.0","1.0.0.255","16777216","16777471","AU","Australia"
"1.0.1.0","1.0.3.255","16777472","16778239","CN","China"
"1.0.4.0","1.0.7.255","16778240","16779263","AU","Australia"
And for those 1st 2 lines I know I need to do 2 reader.ReadLine();'s to ignore them. Any help for a c# newb is welcome! The fields are exactly the same throughout the .csv file, so that would not be a problem. Just don't know if theres an easy way to insert data from a large csv to SQL via c#. Thanks in advance!
EDIT:
What I'm now using, that beautifully gets .csv fields, even within quotes, given TGH's example link. Now just need to insert via SQL connection.
using (TextFieldParser parser = new TextFieldParser(#"C:\StreamReadTest.csv"))
{
parser.SetDelimiters(new string[] { "," });
parser.HasFieldsEnclosedInQuotes = true;
// Skip over header line.
parser.ReadLine();
// Skip field descriptions line.
parser.ReadLine();
while (!parser.EndOfData)
{
string[] fields = parser.ReadFields();
foreach (var value in fields)
{
Console.WriteLine(value);
}
Console.WriteLine("\n");
Console.ReadKey();
}
}
You have several options:
You can create a SqlCommand and run the raw sql string you defined above. Alternatively you could wrap the sql in a stored proc and call it from .Net using Ado.net.
Another approach is to parse the file and save the individual rows through .Net (ado.Net or an ORM like Entity Framework)
I would consider looking into the following library (.net built in csv parser) for parsing the file:
http://coding.abel.nu/2012/06/built-in-net-csv-parser/
I have a report file(.rpt) having text as shown below and this .rpt file get updated every day.
Datum/Uhrzeit,Sta.,Bez.,Unit,TBId,Batch,OrderNr,Mat1,Total1,Mat2,Total2,Mat3,Total3,Mat4,Total4,Mat5,Total5,Mat6,Total6,Summe
41521.755934(04.09.13 18:08:32),TB01,TB01,005,300,9663, ,2,27313.63,0,0.00,0,0.00,3,1776.19,0,0.00,0,0.00,29089.82
41521.797601(04.09.13 19:08:32),TB01,TB01,005,300,9682, ,2,27365.98,0,0.00,0,0.00,3,1780.86,0,0.00,0,0.00,29146.85
41521.839269(04.09.13 20:08:32),TB01,TB01,005,300,9701, ,2,27418.34,0,0.00,0,0.00,3,1785.53,0,0.00,0,0.00,29203.88
41521.880937(04.09.13 21:08:33),TB01,TB01,005,300,9721, ,2,27473.31,0,0.00,0,0.00,3,1790.40,0,0.00,0,0.00,29263.71
41521.922606(04.09.13 22:08:33),TB01,TB01,005,300,9741, ,2,27528.53,0,0.00,0,0.00,3,1795.30,0,0.00,0,0.00,29323.83
41521.964274(04.09.13 23:08:33),TB01,TB01,005,300,9760, ,2,27580.88,0,0.00,0,0.00,3,1799.97,0,0.00,0,0.00,29380.84
41522.005942(05.09.13 00:08:33),TB01,TB01,005,300,9780, ,2,27636.00,0,0.00,0,0.00,3,1804.86,0,0.00,0,0.00,29440.86
Need to extract first and last reading values of every row and need to put that reading in database table.
first reading -- Datum/Uhrzeit
last reading -- Summe
I have used COPY command also but it doesn't take the first value. I want to know which data type to use to extract this value (it is not in normal date formats)???
Also is it not possible just to take these two readings only out of this file and not the whole 20 readings?? Is there any such method available??
I am using PostgreSQL 9.0
Any help would be great.
Assuming that "reading" = "column":
You will need to COPY to a TEMPORARY table where the first column is of type text, not date, since that is an invalid date format.
Then you can do an INSERT INTO teal_table (col1, col2, ...) SELECT some_func(thedate), col2, col3... FROM temptable to transform the temp table contents into correct date data using appropriate SQL and insert it into the real target table.
There are lots of existing examples of this on Stack Overflow, though not for your particular date format. I'm guessing that the date in the parens (...) is the date you want, and that the numbers before are a representation of that date as days since epoch + time since start of day. It'll be easier to just parse the date part, which you can do with:
SELECT to_timestamp(substring('41521.880937(04.09.13 21:08:33)' from '\(.*\)' ), '(DD.MM.YY HH24.MI.SS)');
so that's your some_func for the above.
As for taking only the two desired columns, I already explained that to you before so I'm not going to repeat myself. Short version: Use an ETL tool, re-export the CSV with just those columns, or use a filter program to limit the input.
How do I import data in Excel from a CSV file using C#? Actually, what I want to achieve is similar to what we do in Excel, you go to the Data tab and then select From Text option and then use the Text to columns option and select CSV and it does the magic, and all that stuff. I want to automate it.
If you could head me in the right direction, I'll really appreciate that.
EDIT: I guess I didn't explained well. What I want to do is something like
Excel.Application excelApp;
Excel.Workbook excelWorkbook;
// open excel
excelApp = new Excel.Application();
// something like
excelWorkbook.ImportFromTextFile(); // is what I need
I want to import that data into Excel, not my own application. As far as I know, I don't think I would have to parse the CSV myself and then insert them in Excel. Excel does that for us. I simply need to know how to automate that process.
I think you're over complicating things. Excel automatically splits data into columns by comma delimiters if it's a CSV file. So all you should need to do is ensure your extension is CSV.
I just tried opening a file quick in Excel and it works fine. So what you really need is just to call Workbook.Open() with a file with a CSV extension.
You could open Excel, start recording a macro, do what you want, then see what the macro recorded. That should tell you what objects to use and how to use them.
I beleive there are two parts, one is the split operation for the csv that the other responder has already picked up on, which I don't think is essential but I'll include anyways. And the big one is the writing to the excel file, which I was able to get working, but under specific circumstances and it was a pain to accomplish.
CSV is pretty simple, you can do a string.split on a comma seperator if you want. However, this method is horribly broken, albeit I'll admit I've used it myself, mainly because I also have control over the source data, and know that no quotes or escape characters will ever appear. I've included a link to an article on proper csv parsing, however, I have never tested the source or fully audited the code myself. I have used other code by the same author with success. http://www.boyet.com/articles/csvparser.html
The second part is alot more complex, and was a huge pain for me. The approach I took was to use the jet driver to treat the excel file like a database, and then run SQL queries against it. There are a few limitations, which may cause this to not fit you're goal. I was looking to use prebuilt excel file templates to basically display data and some preset functions and graphs. To accomplish this I have several tabs of report data, and one tab which is raw_data. My program writes to the raw_data tab, and all the other tabs calculations point to cells in this table. I'll go into some of the reasoning for this behavior after the code:
First off, the imports (not all may be required, this is pulled from a larger class file and I didn't properly comment what was for what):
using System.IO;
using System.Diagnostics;
using System.Data.Common;
using System.Globalization;
Next we need to define the connection string, my class already has a FileInfo reference at this point to the file I want to use, so that's what I pass on. It's possible to search on google what all the parameters are for, but basicaly use the Jet Driver (should be available on ANY windows install) to open an excel file like you're referring to a database.
string connectString = #"Provider=Microsoft.Jet.OLEDB.4.0;Data Source={filename};Extended Properties=""Excel 8.0;HDR=YES;IMEX=0""";
connectString = connectString.Replace("{filename}", fi.FullName);
Now let's open up the connection to the DB, and be ready to run commands on the DB:
DbProviderFactory factory = DbProviderFactories.GetFactory("System.Data.OleDb");
using (DbConnection connection = factory.CreateConnection())
{
connection.ConnectionString = connectString;
using (DbCommand command = connection.CreateCommand())
{
connection.Open();
Next we need the actual logic for DB insertion. So basically throw queries into a loop or whatever you're logic is, and insert the data row-by-row.
string query = "INSERT INTO [raw_aaa$] (correlationid, ipaddr, somenum) VALUES (\"abcdef", \"1.1.1.1", 10)";
command.CommandText = query;
command.ExecuteNonQuery();
Now here's the really annoying part, the excel driver tries to detect you're column type before insert, so even if you pass a proper integer value, if excel thinks the column type is text, it will insert all you're numbers as text, and it's very hard to get this treated like a number. As such, excel must already have the column type as the number. In order to accomplish this, for my template file I fill in the first 10 rows with dummy data, so that when you load the file in the jet driver, it can detect the proper types and use them. Then all my forumals that point at my csv table will operate properly since the values are of the right type. This may work for you if you're goals are similar to mine, and to use templates that already point to this data (just start at row 10 instead of row 2).
Because of this, my raw_aaa tab in excel might look something like this:
correlationid ipaddr somenum
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
abcdef 1.1.1.1 5
Note row 1 is the column names that I referenced in my sql queries. I think you can do without this, but that will require a little more research. By already having this data in the excel file, the somenum column will be detected as a number, and any data inserted will be properly treated as such.
Antoher note that makes this annoying, the Jet Driver is 32-bit only, so in my case where I had an explicit 64-bit program, I was unable to execute this directly. So I had the nasty hack of writing to a file, then launch a program that would insert the data in the file into my excel template.
All in all, I think the solution is pretty nasty, but thus far haven't found a better way to do this unfortunatly. Good luck!
You can take a look at TakeIo.Spreadsheet .NET library. It accepts files from Excel 97-2003, Excel 2007 and newer, and CSV format (semicolon or comma separators).
Example:
var inputFile = new FileInfo("Book1.csv"); // could be .xls or .xlsx too
var sheet = Spreadsheet.Read(inputFile);
foreach (var row in sheet)
{
foreach (var cell in row)
{
// do something
}
}
You can remove beginning and trailing empty rows, and also beginning and trailing columns from the imported data using the Normalize() function:
sheet.Normalize();
Sometimes you can find that your imported data contains empty rows between data, so you can use another helper for this case:
sheet.RemoveEmptyRows();
There is a Serialize() function to convert any input to CSV too:
var outfile = new StreamWriter("AllData.csv");
sheet.Serialize(outfile);
If you like to use comma instead of the default semicolon separator in your CSV file, do:
sheet.Serialize(outfile, ',');
And yes, there is also a ToString() function too...
This package is available at NuGet too, just take a look at TakeIo.Spreadsheet.
You can use ADO.NET
http://vbadud.blogspot.com/2008/09/opening-comma-separate-file-csv-through.html
Well, importing from CSV shouldn't be a big deal. I think the most basic method would be to do it using string operations. You could build a pretty fine parser using simple Split() command, and getting the stuff in arrays.
I am reading a text file in C# and trying to save it to a SQL database. I am fine except I don't want the first line, which is the names of the columns, included in the import. What's the easiest way to exclude these?
The code is like this
while (textIn.Peek() != -1)
{
string row = textIn.ReadLine();
string[] columns = row.Split(' ');
Product product = new Product();
product.Column1 = columns[0];
etc.....
product.Save();
}
thanks
If you are writing the code yourself to read in the file and then importing...why don't you just skip over the first line?
Here's my suggestion:
string[] file_rows;
using(var reader=File.OpenText(filepath))
{
file_rows=reader.ReadToEnd().Split("\r\n");
reader.Close();
}
for(var i=1;i<file_rows.Length;i++)
{
var row=file_rows[i];
var cells=row.Split("\t");
....
}
how are you importing the data? if you are looping in C# and inserting them one at a time, construct your loop to skip the first insert!
or just delete the first row inserted after they are there.
give more info, get more details...
Pass a flag into the program (in case in future the first line is also data) that causes the program to skip the first line of text.
If it's the same column names as used in the database you could also parse it to grab the column names from that instead of hard-coding them too (assuming that's what you're doing currently :)).
As a final note, if you're using a MySQL database and you have command line access, you may want to look at the LOAD DATA LOCAL INFILE syntax which lets you import pretty arbitrarily defined CSV data.
For future reference have a look at this awesome package: FileHelpers Library
I can't add links just yet but google should help, it's on sourceforge
It makes our lives here a little easier when people insist on using files as integration