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SQL Bulk Insert in C# not inserting values

I'm completely new to C#, so I'm sure I'm going to get a lot of comments about how my code is formatted - I welcome them. Please feel free to throw any advice or constructive criticisms you might have along the way.
I'm building a very simple Windows Form App that is eventually supposed to take data from an Excel file of varying size, potentially several times per day, and insert it into a table in SQL Server 2005. Thereafter, a stored procedure within the database takes over to perform various update and insert tasks depending on the values inserted into this table.
For this reason, I've decided to use the SQL Bulk Insert method, since I can't know if the user will only insert 10 rows - or 10,000 - at any given execution.
The function I'm using looks like this:
public void BulkImportFromExcel(string excelFilePath)
{
excelApp = new Excel.Application();
excelBook = excelApp.Workbooks.Open(excelFilePath);
excelSheet = excelBook.Worksheets.get_Item(sheetName);
excelRange = excelSheet.UsedRange;
excelBook.Close(0);
try
{
using (SqlConnection sqlConn = new SqlConnection())
{
sqlConn.ConnectionString =
"Data Source=" + serverName + ";" +
"Initial Catalog=" + dbName + ";" +
"User id=" + dbUserName + ";" +
"Password=" + dbPassword + ";";
using (OleDbConnection excelConn = new OleDbConnection())
{
excelQuery = "SELECT InvLakNo FROM [" + sheetName + "$]";
excelConn.ConnectionString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" + excelFilePath + ";Extended Properties='Excel 8.0;HDR=Yes'";
excelConn.Open();
using (OleDbCommand oleDBCmd = new OleDbCommand(excelQuery, excelConn))
{
OleDbDataReader dataReader = oleDBCmd.ExecuteReader();
using (SqlBulkCopy bulkImport = new SqlBulkCopy(sqlConn.ConnectionString))
{
bulkImport.DestinationTableName = sqlTable;
SqlBulkCopyColumnMapping InvLakNo = new SqlBulkCopyColumnMapping("InvLakNo", "InvLakNo");
bulkImport.ColumnMappings.Add(InvLakNo);
sqlQuery = "IF OBJECT_ID('ImportFromExcel') IS NOT NULL BEGIN SELECT * INTO [" + DateTime.Now.ToString().Replace(" ", "_") + "_ImportFromExcel] FROM ImportFromExcel; DROP TABLE ImportFromExcel; END CREATE TABLE ImportFromExcel (InvLakNo INT);";
using (SqlCommand sqlCmd = new SqlCommand(sqlQuery, sqlConn))
{
sqlConn.Open();
sqlCmd.ExecuteNonQuery();
while (dataReader.Read())
{
bulkImport.WriteToServer(dataReader);
}
}
}
}
}
}
}
catch(Exception ex)
{
MessageBox.Show(ex.ToString());
}
finally
{
excelApp.Quit();
}
}
The function runs without errors or warnings, and if I replace the WriteToServer with manual SQL commands, the rows are inserted; but the bulkImport isn't inserting anything.
NOTE: There is only one field in this example, and in the actual function I'm currently running to test; but in the end there will be dozens and dozens of fields being inserted, and I'll be doing a ColumnMapping for all of them.
Also, as stated, I am aware that my code is probably horrible - please feel free to give me any pointers you deem helpful. I'm ready and willing to learn.
Thanks!

I think it would be a very long and messy answer if I commented on your code and also gave pointer sample codes in the same message, so I decided to divide then into two messages. Comments first:
You are using automation to get what? You already have the sheet name as I see it and worse you are doing app.Quit() at the end. Completely remove that automation code.
If you needed some information from excel (like sheet names, column names) then you could use OleDbConnecton's GetOleDbSchemaTable method.
You might do the mapping basically in 2 ways:
Excel column ordinal to SQL table column name
Excel column name to SQL table column name
both would do. In a generic code, assuming you have column names same in both sources, but their ordinal and count may differ, you could get the column names from OleDbConnection schema table and do the mapping in a loop.
You are dropping and creating a table named "ImportFromExcel" for the purpose of temp data insertion, then why not simply create a temp SQL server table by using a # prefix in table name? OTOH that code piece is a little weird, it would do an import from "ImportFromExcel" if it is there, then drop and create a new one and attempt to do bulk import into that new one. In first run, SqlBulkCopy (SBC) would fill ImportFromExcel and on next run it would be copied to a table named (DateTime.Now ...) and then emptied via drop and create again. BTW, naming:
DateTime.Now.ToString().Replace(" ", "_") + "_ImportFromExcel"
doesn't feel right. While it looks tempting, it is not sortable, probably you would want something like this instead:
DateTime.Now.ToString("yyyyMMddHHmmss") + "_ImportFromExcel"
Or better yet:
"ImportFromExcel_" +DateTime.Now.ToString("yyyyMMddHHmmss")
so you would have something that is sorted and selectable for all the imports as a wildcard or looping for some reason.
Then you are writing to server inside a reader.Read() loop. That is not the way WriteToServer works. You wouldn't do reader.Read() but simply:
sbc.WriteToServer(reader);
In my next message e I will give simple schema reading and a simple SBC sample from excel into a temp table, as well as a suggestion how you should do that instead.

Here is the sample for reading schema information from Excel (here we read the tablenames - sheet names with tables in them):
private IEnumerable<string> GetTablesFromExcel(string dataSource)
{
IEnumerable<string> tables;
using (OleDbConnection con = new OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;" +
string.Format("Data Source={0};", dataSource) +
"Extended Properties=\"Excel 12.0;HDR=Yes\""))
{
con.Open();
var schemaTable = con.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
tables = schemaTable.AsEnumerable().Select(t => t.Field<string>("TABLE_NAME"));
con.Close();
}
return tables;
}
And here is a sample that does SBC from excel into a temp table:
void Main()
{
string sqlConnectionString = #"server=.\SQLExpress;Trusted_Connection=yes;Database=Test";
string path = #"C:\Users\Cetin\Documents\ExcelFill.xlsx"; // sample excel sheet
string sheetName = "Sheet1$";
using (OleDbConnection cn = new OleDbConnection(
"Provider=Microsoft.ACE.OLEDB.12.0;Data Source="+path+
";Extended Properties=\"Excel 8.0;HDR=Yes\""))
using (SqlConnection scn = new SqlConnection( sqlConnectionString ))
{
scn.Open();
// create temp SQL server table
new SqlCommand(#"create table #ExcelData
(
[Id] int,
[Barkod] varchar(20)
)", scn).ExecuteNonQuery();
// get data from Excel and write to server via SBC
OleDbCommand cmd = new OleDbCommand(String.Format("select * from [{0}]",sheetName), cn);
SqlBulkCopy sbc = new SqlBulkCopy(scn);
// Mapping sample using column ordinals
sbc.ColumnMappings.Add(0,"[Id]");
sbc.ColumnMappings.Add(1,"[Barkod]");
cn.Open();
OleDbDataReader rdr = cmd.ExecuteReader();
// SqlBulkCopy properties
sbc.DestinationTableName = "#ExcelData";
// write to server via reader
sbc.WriteToServer(rdr);
if (!rdr.IsClosed) { rdr.Close(); }
cn.Close();
// Excel data is now in SQL server temp table
// It might be used to do any internal insert/update
// i.e.: Select into myTable+DateTime.Now
new SqlCommand(string.Format(#"select * into [{0}]
from [#ExcelData]",
"ImportFromExcel_" +DateTime.Now.ToString("yyyyMMddHHmmss")),scn)
.ExecuteNonQuery();
scn.Close();
}
}
While this would work, thinking in the long run, you need column names, and maybe their types differ, it might be an overkill to do this stuff using SBC and you might instead directly do it from MS SQL server's OpenQuery:
SELECT * into ... from OpenQuery(...)

the WriteToServer(IDataReader) is intended to do internally the IDataReader.Read()operation.
using (SqlCommand sqlCmd = new SqlCommand(sqlQuery, sqlConn))
{
sqlConn.Open();
sqlCmd.ExecuteNonQuery();
bulkImport.WriteToServer(dataReader);
}
You can check the MSDN doc on that function, has a working example: https://msdn.microsoft.com/en-us/library/434atets(v=vs.110).aspx

Copying data from one database to another - Out of Memory Exception

I have a task where i want to copy all data from one database to another database & skipping 2 tables. There are more than 200 tables.
I have table structure ready for my 2nd databas.
So as a solution i created a page & on a button click i have below code :-
DataSet ds = new DataSet();
string connectionString = "Data Source=COMP112\\MSSQLSERVER2014;Initial Catalog=HCMBL;Integrated Security=True;Persist Security Info=True";
SqlConnection con = new SqlConnection(connectionString);
//render table name from database
string sqlTable = "SELECT * FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_TYPE='BASE TABLE' and TABLE_Schema='" + Session["SchemaName"].ToString() + "' and TABLE_NAME!='ENTRY' and TABLE_NAME!='OT' and TABLE_NAME!='BL_ENTRY' and TABLE_NAME!='BL_OT'";
con.Open();
SqlDataAdapter da = new SqlDataAdapter();
SqlCommand cmd = new SqlCommand(sqlTable, con);
cmd.CommandType = CommandType.Text;
da.SelectCommand = cmd;
da.Fill(ds);
con.Close();
//render connection string from WebConfig file
string strcon = ConfigurationManager.ConnectionStrings["SPSchema"].ConnectionString;
for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
{
if (!(ds.Tables[0].Rows[i]["TABLE_NAME"].ToString().Contains("Asp")))
{
string deleteQuery = "Truncate table " + Session["SchemaName"].ToString() + "." + ds.Tables[0].Rows[i]["TABLE_NAME"];
con.Open();
SqlCommand cmdDelete = new SqlCommand(deleteQuery, con);
cmdDelete.ExecuteNonQuery();
con.Close();
DataSet dataSet = new DataSet();
SqlConnection conn = new SqlConnection(strcon);
conn.Open();
string selectData = "select * from " + Session["SchemaName"].ToString() + "." + ds.Tables[0].Rows[i]["TABLE_NAME"];
SqlCommand command = new SqlCommand(selectData, conn);
DataTable dataTable = new DataTable();
SqlDataAdapter dataAdapter = new SqlDataAdapter(selectData, conn);
dataAdapter.FillSchema(dataSet, SchemaType.Mapped);
dataAdapter.Fill(dataSet);
dataTable = dataSet.Tables[0];
conn.Close();
if (dataSet.Tables[0].Rows.Count > 0)
{
//Connect to second Database and Insert row/rows.
SqlConnection conn2 = new SqlConnection(connectionString);
conn2.Open();
SqlBulkCopy bulkCopy = new SqlBulkCopy(conn2);
bulkCopy.DestinationTableName = Session["SchemaName"].ToString() + "." + ds.Tables[0].Rows[i]["TABLE_NAME"].ToString();
bulkCopy.WriteToServer(dataTable);
conn2.Close();
}
}
}
As i run the above code after inserting data in less than 10 tables, it gives out of memory exception & program crashes.
How to handle this? I tried increasing the memory capacity of SQL Server but still same error.
Is there any other way to achieve the task?

What you are doing is very far from the best solution. You are using an ASP.NET MVC process to get all data of your entire database into memory, and then outputting it to another database. If your database is anything more than small and trivial, that will most definitely fill your process's alotted memory.
This type of task should never be done through the memory of a process, but rather using some form of Backup/Restore pattern.
You should look into SSIS projects and create an extract, transfer, and load (ETL) solution, which can be triggered from your ASP.NET MVC solution asynchronously.
An SSIS solution can be triggered from C# code in this way:
var app = new Application();
var package = app.LoadPackage("compiled-package.dtsx", null);
var results = package.Execute();
See this question for a little more information (not specifically about duplicating databases, but has information about triggering SSIS packages from code): How to execute an SSIS package from .NET?
Alternatively
You also have the option of running a query against both databases at once, however this requires some additional plumbing to be done. The user account of your ASP.NET MVC solution needs to have access to both databases. If your databases are hosted on different servers, you also need to link one server to the other: Create linked servers
To perform an insert directly from the output of a select, consider this:
string source = "NAME_OF_SOURCE_DATABASE";
string target = "NAME_OF_TARGET_DATABASE";
string schema = Session["SchemaName"].ToString();
string table = ds.Tables[0].Rows[i]["TABLE_NAME"];
// Uncomment this if you need to deal with autoincrement columns
/*string idInsQuery = $"SET IDENTITY_INSERT {target}.{schema}.{table} ON";
var idInsCommand = new SqlCommand(idInsQuery, conn);
idInsCommand.ExecuteNonQuery();*/
string insQuery = $"INSERT INTO {target}.{schema}.{table} SELECT * FROM {source}.{schema}.{table}";
var insCommand = new SqlCommand(insQuery, conn);
insCommand.ExecuteNonQuery();
// Uncomment this if you need to deal with autoincrement columns
/*string idInsQuery2 = $"SET IDENTITY_INSERT {target}.{schema}.{table} OFF";
var idInsCommand2 = new SqlCommand(idInsQuery2, conn);
idInsCommand2.ExecuteNonQuery();*/
This will only work if the table structures are identical. There might be problems with autoincrement ids or columns with default values, too.

This will copy data from a table in database 1 to a table in database 2
Insert into db2.dbo.table2 (col1,col2)
Select col1,col2 from db1.dbo.table1
Run this sql statement and the data will be copied without a round trip to your app.

Let me know if you find my approach is useful.
First of all, why you want to write down one whole application to do this job while SQL Server have inherited property to do it.
My approach would be configure an Linked Server and configure it which tables you want to copy and which one not.
https://learn.microsoft.com/en-us/sql/relational-databases/linked-servers/create-linked-servers-sql-server-database-engine
Secondly, You can just write down simple stored procedure and schedule that in your sql server to push into another server database as per your schedule. In this way you can control it in N number of ways. I mean about controlling any dependencies(Table level or Business level).
To do this in t-sql, you can use the following system stored procedures to schedule a daily job. This example schedules daily at 1:00 AM. See Microsoft help for details on syntax of the individual stored procedures and valid range of parameters.
DECLARE #job_name NVARCHAR(128), #description NVARCHAR(512), #owner_login_name NVARCHAR(128), #database_name NVARCHAR(128);
SET #job_name = N'Some Title';
SET #description = N'Periodically do something';
SET #owner_login_name = N'login';
SET #database_name = N'Database_Name';
-- Delete job if it already exists:
IF EXISTS(SELECT job_id FROM msdb.dbo.sysjobs WHERE (name = #job_name))
BEGIN
EXEC msdb.dbo.sp_delete_job
#job_name = #job_name;
END
-- Create the job:
EXEC msdb.dbo.sp_add_job
#job_name=#job_name,
#enabled=1,
#notify_level_eventlog=0,
#notify_level_email=2,
#notify_level_netsend=2,
#notify_level_page=2,
#delete_level=0,
#description=#description,
#category_name=N'[Uncategorized (Local)]',
#owner_login_name=#owner_login_name;
-- Add server:
EXEC msdb.dbo.sp_add_jobserver #job_name=#job_name;
-- Add step to execute SQL:
EXEC msdb.dbo.sp_add_jobstep
#job_name=#job_name,
#step_name=N'Execute SQL',
#step_id=1,
#cmdexec_success_code=0,
#on_success_action=1,
#on_fail_action=2,
#retry_attempts=0,
#retry_interval=0,
#os_run_priority=0,
#subsystem=N'TSQL',
#command=N'EXEC my_stored_procedure; -- OR ANY SQL STATEMENT',
#database_name=#database_name,
#flags=0;
-- Update job to set start step:
EXEC msdb.dbo.sp_update_job
#job_name=#job_name,
#enabled=1,
#start_step_id=1,
#notify_level_eventlog=0,
#notify_level_email=2,
#notify_level_netsend=2,
#notify_level_page=2,
#delete_level=0,
#description=#description,
#category_name=N'[Uncategorized (Local)]',
#owner_login_name=#owner_login_name,
#notify_email_operator_name=N'',
#notify_netsend_operator_name=N'',
#notify_page_operator_name=N'';
-- Schedule job:
EXEC msdb.dbo.sp_add_jobschedule
#job_name=#job_name,
#name=N'Daily',
#enabled=1,
#freq_type=4,
#freq_interval=1,
#freq_subday_type=1,
#freq_subday_interval=0,
#freq_relative_interval=0,
#freq_recurrence_factor=1,
#active_start_date=20170101, --YYYYMMDD
#active_end_date=99991231, --YYYYMMDD (this represents no end date)
#active_start_time=010000, --HHMMSS
#active_end_time=235959; --HHMMSS
Let me know in case you need more details on this.
Thanks,
Ayan

Basic start with Visual Studio C# and SQL Compact (connect, select, insert)?

I'm trying to learn about C# with SQL CE so that my program can remember stuff.
I have created a database and can connect to it:
SqlCeConnection conn =
new SqlCeConnection(#"Data Source=|DataDirectory|\dbJournal.sdf");
conn.Open();
And it connects right, I guess cause if I rename the dbJournal.sdf to something wrong it doesn't debug right.
Let's say I want to make a simple SELECT query.
(SELECT * FROM tblJournal)
How is that done?
What about a simple insert?
(INSERT TO tblJournal (column1, column2, column2) VALUES
(value1, value2, value3))
I'm used to PHP and MySQL (as you properly can see :o))

#Chuck mentions EntityFramework which simplifies things and does all the work of writing the sql for you.
But there is a basic ADO.NET approach here which I will describe below.
The classes follow a standard pattern so to insert/read from sql server or other databases there are exact replica classes like SqlConnection or OleDbConnection and OleDbCommand etc
This is the most barebones ado.net approach:
using( SqlCeConnection conn =
new SqlCeConnection(#"Data Source=|DataDirectory|\dbJournal.sdf") )
using( SqlCeCommand cmd = conn.CreateCommand() )
{
conn.Open();
//commands represent a query or a stored procedure
cmd.CommandText = "SELECT * FROM tblJournal";
using( SqlCeDataReader rd = cmd.ExecuteReader() )
{
//...read
}
conn.Close();
}
Then to read data :
while (rd.Read())
{//loop through the records one by one
//0 gets the first columns data for this record
//as an INT
rd.GetInt32(0);
//gets the second column as a string
rd.GetString(1);
}
A nice and quicker way to read data is like this:
using( SqlCeDataAdapter adap =
new SqlCeDataAdapter("SELECT * FROM tblJournal", "your connection") )
{
//the adapter will open and close the connection for you.
DataTable dat = new DataTable();
adap.Fill(dat);
}
This gets the entire data in one shot into a DataTable class.
To insert data :
SqlCeCommand cmdInsert = conn.CreateCommand();
cmdInsert.CommandText = "INSERT TO tblJournal (column1, column2, column2)
VALUES (value1, value2, value3)";
cmdInsert.ExecuteNonQuery();

If you just start learning that i will suggest you to use LINQ to make that queries.
Here is MSDN article showing features of LINQ.
http://msdn.microsoft.com/en-us/library/bb425822.aspx
Using LINQ it will be simple to do every query. For example, you can write your select query like this
from journal in TblJournal select journal
or just
context.TblJournal

also in order to improve performence , you better keep the conncection open all the time when working with SQL CE (as opposed to other standard sql databases)

SQL connection string for microsoft access 2010 .accdb

I am doing a simple login form using winforms and access 2010 database (.accdb) in C#.
I have the following code and it seems that the connection string is wrong. I have tried searching and found that .Jet is for access 07?? but this doesnt seem to work too.
i am an amateur at databases (code referred from msdn). I am having trouble understand which should i use for this example too.
access table name: haha
ID (PK) | password
-----------------------
1 | testing
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection(#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\BC207\test.accdb");
System.Data.SqlClient.SqlCommand comm = new System.Data.SqlClient.SqlCommand();
comm.CommandText = "SELECT HAHA(*) FROM password";
comm.CommandType = CommandType.Text;
comm.Connection = conn;
conn.Open();
Object returnValue = comm.ExecuteScalar();
conn.Close();
MessageBox.Show((string)returnValue);
edited: the table's name is password, and the field that i want to get the value is ID.
SQL statement i wrote it as : SELECT ID FROM password
and yes, only one record in only one field in the table as the primary key.
anyway the problem is that the program hangs upon execution on the first line
-> Keyword not supported: 'provider'.
so i figured that I have a wrong connection string..

For Acces databases (.mdb, .accdb, etc...), you want to use OleDbConnection, not SqlConnection (SQL Server), like this:
conn = new System.Data.OleDb.OleDbConnection(#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\BC207\test.accdb")

Edit: as pointed out, for access OleDbConnection should be used, not SqlConnection...
you can use a much more compact way and also be sure connection is closed and disposed in any possible case even when exceptions are thrown, by using the using statements:
your query text was also, probably wrong as others have suggested...
using (var conn = new OleDbConnection(#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\BC207\test.accdb"))
using (var comm = conn.CreateCommand())
{
comm.CommandText = "SELECT password FROM HAHA";
comm.CommandType = CommandType.Text;
conn.Open();
var returnValue = comm.ExecuteScalar();
MessageBox.Show(returnValue.ToString());
}
Edit: are you sure the table HAHA only contains one row? Because the ExecuteScalar returns only one value, if you want to get 1 column but from many records you could use a DataReader or a DataSet...

comm.CommandText = "SELECT HAHA(*) FROM password";
It´s wrong.
"SELECT password FROM HAHA"

Your SQL statement should be,
SELECT * from HAHA
OR
SELECT [Password] From HAHA
EDIT:
You should change the ConnectionString.

Error executing update over OLEDB from C#

I am using OLEDB to Update data in .dbf database from c#.
I get Error: System.Data.OleDb.OleDbException {"Undefined function 'replace' in expression."} on ExecuteNonQuery.
How can I make this work with least changes, i need to replace double quotes with single quotes in many files, so i have to automate this process.
Should I try ODBC or something else for .dbf database?
Help please!
string connString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + directory +";Extended Properties=dBASE III;";
OleDbConnection conn = new OleDbConnection(connString);
conn.Open();
OleDbCommand cmd = conn.CreateCommand();
cmd.CommandType = System.Data.CommandType.Text;
cmd.CommandText = "update Addres_1 set NAME_ENU = replace(NAME_ENU, 'a', 'b') where NAME_ENU like '*a*'";
int res = cmd.ExecuteNonQuery();

Replace is not supported by used data provider.
I will update answer if and when i find out how to do this in fast and simple way on large dataset.