I want to search the records that have 3 or more '#'.
In MSAccess I can Write this and show me the results:
SELECT * FROM AlmLotes WHERE Lote LIKE '[#][#][#]*';
But in C# don't works.
DataTable dtResultats = new DataTable();
string strConnectionSource = MYCONNECTIONSTRING
OleDbConnection connAccess = new OleDbConnection(strConnectionSource);
connAccess.Open();
string strSQL = "SELECT * FROM AlmLotes WHERE Lote LIKE '[#][#][#]*'";
OleDbCommand cmd = new OleDbCommand(strSQL, connAccess);
OleDbDataAdapter myDataAdapter = new OleDbDataAdapter(cmd);
dtResultats = new DataTable();
try
{
myDataAdapter.Fill(dtResultats);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
for (int i = 0; i < dtResultats.Rows.Count; i++)
{
var rows = dtResultats.Rows[i];
for (int z = 0; z < dtResultats.Columns.Count; z++)
{
Console.WriteLine(dtResultats.Columns[z].ColumnName + ": " + rows[z] + Environment.NewLine);
}
}
Console.ReadKey();
The SQL Query in MSAcces show me 5 results.
THE SQL QUery in C# show me 0 results.
Try this:
string strSQL = #"SELECT * FROM AlmLotes WHERE Lote LIKE LIKE '[[#]%'";
So Ms Access use *, but C# OleDb use %. You can replace * to %.
string strSQL = #"SELECT * FROM AlmLotes WHERE Lote LIKE '###%'";
The solution are the Parameters:
string strSQL = "SELECT * FROM AlmLotes WHERE Lote LIKE #PARAM1";
OleDbCommand cmd = new OleDbCommand(strSQL, connAccess);
OleDbParameter param = cmd.CreateParameter();
param.DbType = DbType.String;
param.Direction = ParameterDirection.Input;
param.OleDbType = OleDbType.VarChar;
param.ParameterName = "PARAM1";
param.Value = "###%";
cmd.Parameters.Add(param);
OleDbDataAdapter myDataAdapter = new OleDbDataAdapter(cmd);
dtResultats = new DataTable();
Related
I'm trying this code but it shows an error on da.Fill(dt)
No value given for one or more required parameters.
Why does it show that error? I clearly check all names of databases and tables and fields, they all are correct and I'm using date/time field for datetime.
Can you help me with this?
string conn = #"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\ahmed\OneDrive\Documents\shop.accdb";
OleDbConnection ccc = new OleDbConnection(conn);
ccc.Open();
string css = "SELECT * from tbl3 Where dateitem between '" + dateTimePicker1.Value.ToString() + "%' AND '" + dateTimePicker2.Value.ToString()+"%'";
OleDbCommand non = new OleDbCommand(css, ccc);
OleDbDataAdapter da = new OleDbDataAdapter(non);
DataTable dt = new DataTable();
da.Fill(dt);
count = Convert.ToInt32(dt.Rows.Count.ToString());
dataGridView1.DataSource = new BindingSource(dt, null);
As others have mentioned you should use the parameters instead of hard coding the values.
using (OleDbConnection conn = new OleDbConnection(#"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\Users\ahmed\OneDrive\Documents\shop.accdb"))
{
conn.Open();
// DbCommand also implements IDisposable
using (OleDbCommand cmd = conn.CreateCommand())
{
var param1 = new OleDbParameter("#DateTimePicker1", OleDbType.DBDate); //you may have to play with different types
param1.Value = dateTimePicker1.Value;
cmd.Parameters.Add(param1);
var param2 = new OleDbParameter("#DateTimePicker2", OleDbType.DBDate);
param2.Value = dateTimePicker2.Value;
cmd.Parameters.Add(param2);
cmd.CommandText = "SELECT * from tbl3 Where datetime >= #DateTimePicker1 and datetime <= #DateTimePicker2";
OleDbDataAdapter da = new OleDbDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
count = Convert.ToInt32(dt.Rows.Count.ToString());
dataGridView1.DataSource = new BindingSource(dt, null);
}
}
What I'm missing?
I've got error:
Sqlexception was unhandled by usercode
SqlConnection con = new SqlConnection(MyConnectionString);
SqlCommand objCmd;
con.Open();
SqlDataReader dtReader;
String strSQL;
strSQL = "SELECT * FROM " + DropDownList1.SelectedValue + "'";
objCmd = new SqlCommand(strSQL, con);
dtReader = objCmd.ExecuteReader();
//*** BindData to GridView ***//
GridView3.DataSource = dtReader;
GridView3.DataBind();
dtReader.Close();
dtReader = null;
Try this ,
strSQL = "SELECT * FROM " + DropDownList1.SelectedValue;
ie., just remove ' from the query string.
Then add the following code at the end.
GridView3.DataSource = dtReader;
GridView3.DataSourceID = String.Empty;
GridView3.DataBind();
this code works now
SqlConnection con = new SqlConnection(MyConnectionString);
SqlCommand objCmd;
con.Open();
SqlDataReader dtReader;
String strSQL;
strSQL = "SELECT * FROM " + DropDownList1.SelectedValue ;
objCmd = new SqlCommand(strSQL, con);
dtReader = objCmd.ExecuteReader();
GridView3.DataSource = dtReader;
GridView3.DataSourceID = String.Empty;
GridView3.DataBind();
dtReader.Close();
dtReader = null;
How to count the number of rows from sql table in c#?
I need to extract some data from my database...
You may try like this:
select count(*) from tablename where columname = 'values'
C# code will be something like this:-
public int A()
{
string stmt = "SELECT COUNT(*) FROM dbo.tablename";
int count = 0;
using(SqlConnection thisConnection = new SqlConnection("Data Source=DATASOURCE"))
{
using(SqlCommand cmdCount = new SqlCommand(stmt, thisConnection))
{
thisConnection.Open();
count = (int)cmdCount.ExecuteScalar();
}
}
return count;
}
You need to make a database connection from c# first. Then, you need to pass below query as commandText.
Select count(*) from TableName
Use ExecuteScalar/ExecuteReader to get the returned count.
Do you means likes this ?
SELECT COUNT(*)
FROM yourTable
WHERE ....
You can make global function that you can use all the time as
public static int GetTableCount(string tablename, string connStr = null)
{
string stmt = string.Format("SELECT COUNT(*) FROM {0}", tablename);
if (String.IsNullOrEmpty(connStr))
connStr = ConnectionString;
int count = 0;
try
{
using (SqlConnection thisConnection = new SqlConnection(connStr))
{
using (SqlCommand cmdCount = new SqlCommand(stmt, thisConnection))
{
thisConnection.Open();
count = (int)cmdCount.ExecuteScalar();
}
}
return count;
}
catch (Exception ex)
{
VDBLogger.LogError(ex);
return 0;
}
}
This works for me
using (var context = new BloggingContext())
{
var blogs = context.Blogs.SqlQuery("SELECT * FROM dbo.Blogs").ToList();
}
For more information consult: https://learn.microsoft.com/es-es/ef/ef6/querying/raw-sql?redirectedfrom=MSDN
Use this its working
string strQuery = "SELECT * FROM staff WHERE usertype='lacturer'";
connect.Open();
SqlCommand cmd = new SqlCommand(strQuery, connect);
SqlDataAdapter OleDbDa = new SqlDataAdapter(cmd);
DataSet dsData = new DataSet();
OleDbDa.Fill(dsData);
connect.Close();
std.Text = dsData.Tables[0].Rows.Count.ToString();
I used this method in my own application to count the number of active users within the program. This can be easily manipulated for your own use.
con.open();
string ActiveUsers = "SELECT * FROM Devices WHERE Status='" + "Online" + "'";
SqlCommand cmd = new SqlCommand(ActiveUsers, con);
SqlDataAdapter sda = new SqlDataAdapter(cmd);
DataSet ds = new DataSet();
sda.Fill(ds);
con.Close();
Users.Text = ds.Tables[0].Rows.Count.ToString();
i need update some column in datagridview to database. but don't update to database.
step one: i select datetime from datetimepicker.
step two: show datetime on datagridview.
step tree: i need update/edit on datagridview to database.
Display on Datagridview.
EmpNo fName ChkDate ChkIn ChkOut
00001 Al 01/10/2012 08:02 17:04
00002 Bik 01/10/2012 07:43 18:35
i need update fields "ChkIn" to database.
Code
SqlConnection Conn;
SqlCommand cmd = new SqlCommand();
SqlDataAdapter da;
DataTable dt = new DataTable();
DataSet ds = new DataSet();
StringBuilder sb = new StringBuilder();
string appConn = ConfigurationManager.ConnectionStrings["connDB"].ConnectionString;
int i;
for (i = 1; i < dgvShow.Rows.Count; i++)
{
if (dgvShow.Rows.Count > 0)
{
SqlConnection conn = new SqlConnection(appConn);
string sql = "UPDATE [WebSP].[dbo].[filesTA]"
+ "SET [filesTA].ChkIn = replace(convert(nvarchar(10),'" + dgvShow.Rows[i].Cells[3].Value + "',102),'.',':')"
+ "FROM [WebSP].[dbo].[filesTA]"
+ "WHERE [filesTA].ChkDate = '" + dateTimePicker.Value.ToString("yyyy-MM-dd") + "' and [filesTA].EmpNo = '" + dgvShow.Rows[i].Cells[0].Value + "'";
da = new SqlDataAdapter(sql, Conn);
DataSet ds = new DataSet();
da.Fill(ds);
Conn.Close();
dgvShow.DataSource = ds;
da.Update(ds);
}
}
Error: Update unable to find TableMapping['Table'] or DataTable 'Table'.
I try other code:
Conn = new SqlConnection();
if (Conn.State == ConnectionState.Open)
{
Conn.Close();
}
Conn.ConnectionString = appConn;
Conn.Open();
SqlDataAdapter adapter = new SqlDataAdapter("SELECT * FROM [filesTA]", appConn);
adapter.UpdateCommand = new SqlCommand("UPDATE [WebSP].[dbo].[filesTA]"
+ "SET [filesTA].ChkIn = replace(convert(nvarchar(10),#cIn,102),'.',':')"
+ "FROM [WebSP].[dbo].[filesTA]"
+ "WHERE [filesTA].ChkDate = #cDate and [filesTA].EmpNo = #eNo", Conn);
adapter.UpdateCommand.Parameters.Add("#cIn", SqlDbType.NVarChar, 10, "ChkIn");
adapter.UpdateCommand.Parameters.Add("#cDate", SqlDbType.NVarChar, 10, "ChkDate");
adapter.UpdateCommand.Parameters.Add("#eNo", SqlDbType.NVarChar, 10, "EmpNo");
DataSet ds = new DataSet();
adapter.Fill(ds);
dgvShow.DataSource = ds;
adapter.Update(ds);
this code not save to database.
Thanks for your time. :D
Type Database:
ChkIn and ChkDate Type DateTime,EmpNo Type NUMERIC
I try
int i;
for (i = 1; i < dgvShow.Rows.Count; i++)
{
if (dgvShow.Rows.Count > 0)
{
using (Conn = new SqlConnection(appConn))
{
Conn.Open();
string sql = "UPDATE [WebSP].[dbo].[filesTA]" +
"SET [filesTA].ChkIn = replace(convert(nvarchar(10),#cIn,102),'.',':')" +
"FROM [WebSP].[dbo].[filesTA]" +
"WHERE [filesTA].ChkDate = #cDate and [filesTA].EmpNo = #eNo";
SqlCommand cmd = new SqlCommand(sql, Conn);
cmd.Parameters.Add("#cIn", SqlDbType.DateTime, 10, "ChkIn").Value = Convert.ToDateTime(dgvShow.Rows[i].Cells[3].Value).ToString();
cmd.Parameters.Add("#cDate", SqlDbType.DateTime, 10, "ChkDate").Value = Convert.ToDateTime(dateTimePicker.Value.ToString()).ToString();
cmd.Parameters.Add("#eNo", SqlDbType.Decimal, 10, "EmpNo").Value = Convert.ToDecimal(dgvShow.Rows[i].Cells[0].Value).ToString();
cmd.ExecuteNonQuery();
}
}
}
Error: Conversion failed when converting date and/or time from character string. T__T
You could try to get rid of the SqlDataAdapter using directly a SqlCommand
Using(Conn = new SqlConnection(appConn))
{
Conn.Open();
string sql = "UPDATE [WebSP].[dbo].[filesTA] " +
"SET [filesTA].ChkIn = replace(convert(nvarchar(10),#cIn,102),'.',':') " +
"FROM [WebSP].[dbo].[filesTA] " +
"WHERE [filesTA].ChkDate = #cDate and [filesTA].EmpNo = #eNo";
SqlCommand cmd = new SqlCommand(sql, Conn);
cmd.Parameters.Add("#cIn", SqlDbType.NVarChar, 10, "ChkIn").Value =
dgvShow.Rows[i].Cells[3].Value;
cmd.Parameters.Add("#cDate", SqlDbType.NVarChar, 10, "ChkDate").Value =
dateTimePicker.Value.ToString("yyyy-MM-dd") ;
cmd.Parameters.Add("#eNo", SqlDbType.NVarChar, 10, "EmpNo").Value =
dgvShow.Rows[i].Cells[0].Value ;
cmd.ExecuteNonQuery();
}
Of course, when using parameters, we need to set their values before running the command.
However I really don't understand well the code to update the ChkIn field. That field (according to the Parameter type) is a nvarchar, then why don't you try to format your #cIn value directly in code and avoid the use of Sql Server Replace and Convert functions? Also the 102 is a Date Style. It is used to format Date expressions as strings with the yy.mm.dddd pattern, but you have a string that contains only time info.
For example
After your last edit - changed to this
DateTime chkIN = Convert.ToDateTime(dgvShow.Rows[i].Cells[3].Value);
DateTime chkDate = Convert.ToDateTime(dateTimePicker.Value.ToString("yyyy-MM-dd"));
decimal empNo = Convert.ToDecimal(dgvShow.Rows[i].Cells[0].Value) ;
cmd.Parameters.Add("#cIn", SqlDbType.DateTime).Value = chkIN;
cmd.Parameters.Add("#cDate", SqlDbType.DateTime).Value = chkDate;
cmd.Parameters.Add("#eNo", SqlDbType.Decimal).Value = empNo;
Also the syntax used in query could be the source of other problems, but I need to see your connection string.
I a Parameter ordial = 1 error on this code.
Can anyone explain it in this context? dbCon is correct as I can insert data to the database just trying out how to get it back no.
if (dbCon.State == ConnectionState.Closed)
{
dbCon.Open(); ;
}
SqlCeParameter vetidfromdropbox = new SqlCeParameter("#vetidfromdropbox", SqlDbType.Int);
vetidfromdropbox.Value = 2;
SqlCeCommand mySQLCommand = new SqlCeCommand("SELECT * FROM vets WHERE vetID = #vetidfromdropbox", dbCon);
SqlCeDataReader rdata = mySQLCommand.ExecuteReader();
if(rdata.Read()){
editNameTextbox.Text = (String)rdata["vetName"];
editSurnameTextbox.Text = (String)rdata["vetSurname"];
editCompanyNameTextbox.Text = (String)rdata["vetCompanyName"];
editPractiseAddTextBox.Text = (String)rdata["vetPractiseAddress"];
editMobileTextbox.Text = (String)rdata["vetMobile"];
editOtherTextbox.Text = (String)rdata["vetOther"];
editNotesTextbox.Text = (String)rdata["vetNotes"];
}else{
MessageBox.Show(" There has been an error with Read() ");
}
if (dbCon.State == ConnectionState.Open)
{
dbCon.Close();
}
You didn't add parameter to your SQL command:
var vetidfromdropbox = new SqlCeParameter("#vetidfromdropbox", SqlDbType.Int);
vetidfromdropbox.Value = 2;
var mySQLCommand = new SqlCeCommand(
"SELECT * FROM vets WHERE vetID = #vetidfromdropbox", dbCon);
mySQLCommand.Parameters.Add(vetidfromdropbox);
You can use AddWithValue to simplify the syntax:
var mySQLCommand = new SqlCommand(
"SELECT * FROM vets WHERE vetID = #vetidfromdropbox", dbCon);
mySQLCommand.Parameters.AddWithValue("vetidfromdropbox", 2);
Side note: use using on your sql connection and command to guarantee disposal and to simplify code.