Re: Select count and select - Database Discussion Boards

Care Career19-Apr-07 1:41

19-Apr-07 1:41

Hi
I have one table Employee having fields id,Name,Salary (id is primary Key)
I have another table Phone having fields id,phone.(id is forign key)

1)using these two tables I want to get all the details of Employee who does not have phone Nos.

2)& I want details of all employees who have more than 2 phone nos.

Plz send these queries as soon as possible.

Thanks

Care Career

Re: SQL Query

kubben19-Apr-07 2:02

kubben

19-Apr-07 2:02

1) Select e.* from employee e
left join Phone p on e.id = p.id
where p.id is null

2)
select e.id,p.phone from employee e
join phone p on e.id = p.id
group by e.id, p.phone
having count(*) > 1

You should probably buy a good sql book.

Ben

Insert Date using oledbcommand

cocoonwls19-Apr-07 0:18

cocoonwls

19-Apr-07 0:18

Hi,

In my app, I would like to insert data into MS Access. In my databse, have 3 columns-(datetime,datetime,text).Below is my code

strInsert = "INSERT INTO Alarms(Date,Time,description)VALUES ('"+dateTimePicker1.Value.Date+"', '"+dateTimePicker1.Value.Date+"' , 'err orlog')";
:
:
conx.open();
OleDbCommand cmd1 = new OleDbCommand(strInsert, conx);
cmd1.ExecuteNonQuery();
conx.close();

I am getting this error message - "OleDbException was unhandled". I am not idea what was wrong.Can anyone guide me to solve this error.

thanks in advance

cocoonwls

Re: Insert Date using oledbcommand

Kschuler19-Apr-07 10:27

Kschuler

19-Apr-07 10:27

First you may want to figure out which line is cauing the error. If it is the conx.open() line then you have a problem with the connection. If it is the ExecuteNonQuery line then it is probably teh SQL. Is there more to teh error message? I've never inserted a datetime object before, but you may want to lookup the format it needs to be in and whether or not you need the single quotes around it.

Hope this helps.

--------------------------------------------------
Play Nation States and join The Code Project region with the password: byalmightybob

Re: Insert Date using oledbcommand

cocoonwls19-Apr-07 15:52

cocoonwls

19-Apr-07 15:52

Hi,
Thanks for your reply.I have found the mistake.The Date value should put "#" symbol infront and after the variable, as below:

strInsert = "INSERT INTO Alarms (DateIn, TimeIn, Description) VALUES (#" +dateTimePicker1.Value+ "#,#" +dateTimePicker1.Value+ "#,'e')"

regards
cocoonwls

Select count and select

N a v a n e e t h18-Apr-07 22:37

N a v a n e e t h

18-Apr-07 22:37

Select count(*) From TableName
Select count(column) From TableName
Select * From TableName

In these queries which will work more fast ? What could be the reason ?

printf("Navaneeth!!")

www.w3hearts.com

Re: Select count and select

Pete O'Hanlon18-Apr-07 22:50

Pete O'Hanlon

18-Apr-07 22:50

DooDooo wrote:
In these queries which will work more fast ?

Try them out to find out. Once you've run them, have a think about what each one is actually doing and how many rows they are returning. Hint - try the second count on a nullable column.

Deja View - the feeling that you've seen this post before.

Re: Select count and select

Colin Angus Mackay18-Apr-07 22:56

Colin Angus Mackay

18-Apr-07 22:56

DooDooo wrote:
In these queries which will work more fast ? What could be the reason ?

They all do different things. It is an invalid comparison.

Upcoming events:
* Glasgow: Introduction to AJAX (2nd May), SQL Server 2005 - XML and XML Query Plans, Mock Objects, SQL Server Reporting Services...

Never write for other people. Write for yourself, because you have a passion for it. -- Marc Clifton

My website

Re: Select count and select

N a v a n e e t h19-Apr-07 1:22

N a v a n e e t h

19-Apr-07 1:22

Ya I know all three queries are doing different things. What I mean to say was my friend told that select count(*) will take much time that executing select * from table. Because first it will select all data from table and finds the count. I just wanted to know whether this is rite or not ?

printf("Navaneeth!!")

www.w3hearts.com

Re: Select count and select

Colin Angus Mackay19-Apr-07 1:46

Colin Angus Mackay

19-Apr-07 1:46

DooDooo wrote:
What I mean to say was my friend told that select count(*) will take much time that executing select * from table. Because first it will select all data from table and finds the count. I just wanted to know whether this is rite or not ?

You also have to take in to consideration network bandwidth used. SELECT COUNT(*) FROM MyTable returns a single value. SELECT * FROM MyTable returns the entire contents of the table.

Also, I'd guess the COUNT(*) would be able to take into account an index so it wouldn't actually have to read every single row, just one of the indexes (which would be a lot less data)

Re: Select count and select

N a v a n e e t h19-Apr-07 2:58

N a v a n e e t h

19-Apr-07 2:58

Thank you very much

printf("Navaneeth!!")

www.w3hearts.com

data moving

tradakad18-Apr-07 22:16

tradakad

18-Apr-07 22:16

Hi, All.

example: I have two databases. mySQL and MS SQL. I have to load some data from MySQL into MS SQL.
I can't use SSIS or something like that because my version of MS SQL Server hasn't it. so I must write my pwn programm foor this task.

I write two classes - first fro working with MySQL and second for MS SQL.

----------
MySQL
----------
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using MySql.Data.MySqlClient;

public class MySqlClass
{
public MySqlClass()
{
//
// TODO: Add constructor logic here
//
}

static public MySqlConnection myConnection = null;

public string GetConnection(string con_str)
{
string connection_string = string.Empty;

if (con_str.Length == 0)
connection_string = System.Configuration.ConfigurationManager.ConnectionStrings[2].ToString();
else
connection_string = con_str;

try
{
myConnection = new MySqlConnection(connection_string);
myConnection.Open();
}
catch (MySqlException err)
{
return "Erron in connection :" + err.Message;
}

finally
{
if (myConnection != null)
myConnection.Close();
}

return null;
}

public DataSet MySqlOpen(string sql_cmd)
{
if (myConnection != null)
myConnection.Close();

myConnection.Open();

MySqlDataAdapter myDataAdapter = new MySqlDataAdapter(sql_cmd, myConnection);
DataSet myDataSet = new DataSet();

myDataAdapter.Fill(myDataSet);

myConnection.Close();

return myDataSet;

}

public void MySqlRun(string sql_cmd)
{
if (myConnection != null)
myConnection.Close();

myConnection.Open();
MySqlCommand cmd = new MySqlCommand(sql_cmd, myConnection);
cmd.ExecuteNonQuery();
myConnection.Close();

}

public void MySqlRunTransaction(string[] queries)
{
MySqlTransaction trans = null;

if (myConnection != null)
myConnection.Close();

try
{
myConnection.Open();

trans = myConnection.BeginTransaction();

MySqlCommand cmd = new MySqlCommand();

cmd.Connection = myConnection;
cmd.Transaction = trans;

foreach (string query in queries)
{
cmd.CommandText = query;
cmd.ExecuteNonQuery();
}
trans.Commit();
}
catch (MySqlException SqlErr)
{
if (trans != null)
{
trans.Rollback();
}
throw new Exception("An error occured while transaction", SqlErr);
//return;
}
finally
{
if (myConnection != null)
{
myConnection.Close();
}
}
}

}

----------

----------
MS SQL
----------
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;

public class SqlClass
{
public SqlClass()
{
//
// TODO: Add constructor logic here
//
}

static public SqlConnection myConnection = null;

public string GetConnection(string con_str)
{

string connection_string = string.Empty;

if (con_str.Length == 0)
connection_string = System.Configuration.ConfigurationManager.ConnectionStrings[3].ToString();
else
connection_string = con_str;

try
{
myConnection = new SqlConnection(connection_string);
myConnection.Open();

}
catch (SqlException err)
{
return "Erron in connection :" + err.Message;
}

finally
{
if (myConnection != null)
myConnection.Close();
}

return null;
}

public DataSet SqlOpen(string sql_cmd)
{
if (myConnection != null)
myConnection.Close();

myConnection.Open();

SqlDataAdapter myDataAdapter = new SqlDataAdapter(sql_cmd, myConnection);
DataSet myDataSet = new DataSet();

myDataAdapter.Fill(myDataSet);

myConnection.Close();

return myDataSet;

}

public void SqlRun(string sql_cmd)
{
if (myConnection != null)
myConnection.Close();

myConnection.Open();
SqlCommand cmd = new SqlCommand(sql_cmd, myConnection);
cmd.ExecuteNonQuery();
myConnection.Close();

}

public void SqlRunTransaction(string[] queries)
{
SqlTransaction trans = null;

if (myConnection != null)
myConnection.Close();

try
{
myConnection.Open();

trans = myConnection.BeginTransaction();

SqlCommand cmd = new SqlCommand();

cmd.Connection = myConnection;
cmd.Transaction = trans;

foreach (string query in queries)
{
cmd.CommandText = query;
cmd.ExecuteNonQuery();
}
trans.Commit();
}
catch (SqlException SqlErr)
{
if (trans != null)
{
trans.Rollback();
}
throw new Exception("An error occured while transaction", SqlErr);
//return;
}
finally
{
if (myConnection != null)
{
myConnection.Close();
}
}
}

}

----------

so in my main unit i declared them

public MySqlClass mys = new MySqlClass();
public SqlClass ms = new SqlClass();

and when I wanna get result from MySQL i do -

DataSet myDataSet = new DataSet();

try
{
myDataSet = mys.MySqlOpen(txtMySQLQuery.Text);
}
catch (MySqlException err)
{
Response.Write(err.ToString());
}

so I have a dataset with data (now myDataSet contains result of my query isn't ?)

my question - HOW can I load a data from this dataset into another database and table? i think I should use something like dataadapter or dataset but i'm not sure. and can I use ms.SqlRun for this (i declared it before) or I should use some another way?

thanx a lot!!!

--
"Success is simple. Do what's right, the right way, at the right time."

best regards,
tradakad

Re: data moving

Colin Angus Mackay18-Apr-07 22:25

Colin Angus Mackay

18-Apr-07 22:25

tradakad wrote:
I can't use SSIS or something like that because my version of MS SQL Server hasn't it.

SSIS is just a rebranded version of DTS. Use DTS.

Re: data moving

tradakad18-Apr-07 22:47

tradakad

18-Apr-07 22:47

I haven't got it too Frown | :(

can i FREE download it? i mean for my MS SQL Server Express Edition version?

thanx!

--
"Success is simple. Do what's right, the right way, at the right time."

best regards,
tradakad

Re: data moving

Mike Dimmick19-Apr-07 3:17

Mike Dimmick

19-Apr-07 3:17

I'm fairly sure that's not true, otherwise why would there be a separate download for the legacy DTS runtime? SSIS is effectively the next version of DTS (in development and Beta it was still called DTS and the process is called MsDtsServer.exe), but is not fully compatible with 2000's DTS.

Yes, if targetting SQL Server 2000 and optionally 2005, use DTS. Otherwise use SSIS.

SQL Server 2005 Express Edition doesn't have SSIS. That's only included in Standard and Enterprise Editions (and of course Developer Edition which is Enterprise with a restricted licence, the capability to run on client Windows operating systems, and autoshrink turned on). DTS was also not present in MSDE 2000.

Stability. What an interesting concept. -- Chris Maunder

Re: data moving

Colin Angus Mackay19-Apr-07 3:25

Colin Angus Mackay

19-Apr-07 3:25

Mike Dimmick wrote:
I'm fairly sure that's not true, otherwise why would there be a separate download for the legacy DTS runtime?

It is a rebranded DTS. As you pointed out they rebranded it for SQL Server 2005 half way through the development cycle - hence there are references to DTS in the code.

Mike Dimmick wrote:
SQL Server 2005 Express Edition doesn't have SSIS. That's only included in Standard and Enterprise Editions (and of course Developer Edition which is Enterprise with a restricted licence, the capability to run on client Windows operating systems, and autoshrink turned on). DTS was also not present in MSDE 2000.

True. I made an assumption that it was one of the full server or developer products that was being used.

update statement syntax error

rkherath18-Apr-07 21:45

rkherath

18-Apr-07 21:45

HI all,

my application is to read a access dtbase tables which has the same format of columns. but it gives an update statement Syntax error. please help

OleDbConnection con = new OleDbConnection();
OleDbDataAdapter da = new OleDbDataAdapter();
OleDbCommand selcom = new OleDbCommand();
OleDbCommand upcom = new OleDbCommand();
DataSet ds = new DataSet();

private void button1_Click(object sender, EventArgs e)
{
string path = txtSelectLoc.Text;
processTables(path);
//UpdateMethod(path, "GRO");

}

void processTables(string path)
{

DataTable dt = new DataTable();
dt = sqlConnection().Tables[0];

foreach (DataRow dr in dt.Rows)
{

UpdateMethod(path,"WWA");

}

}

DataSet sqlConnection()
{
SqlCommand sqlSelect = new SqlCommand();
SqlConnection SQLcon = new SqlConnection("data source=Ruwandi;initial catalog=MIS;user id=sa");
SqlDataAdapter SQLda = new SqlDataAdapter();
sqlSelect.CommandText= "Select Alias from mfLocation where Alias<>''";
sqlSelect.Connection=SQLcon;
SQLda.SelectCommand = sqlSelect;
SQLda.Fill(ds);
return ds;
//dataGridView1.DataSource = ds.Tables[0];
}

private void UpdateMethod(string path,string tbName)
{
con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + path +
";Jet OLEDB:Database Password=sanuja";
DataTable dt = SelectMethod(tbName).Tables[0];
upcom.Connection = con;
con.Open();
int x = 0;
foreach (DataRow dr in dt.Rows)
{

x = x + 1;
string str = dr["CATEGORY"].ToString();
dr.AcceptChanges();
upcom.CommandText = "update CON_"+ tbName +" set BGT_APR=0,BGT_MAY=0,BGT_JUN=0,BGT_JUL=0,BGT_AUG=0,BGT_SEP=0,BGT_OCT=0,BGT_NOV=0,BGT_DEC=0,BGT_JAN=0,BGT_FEB=0,BGT_MAR=0,BUDGETED=0,BUDGET_PES=0," +
"NET_APR=0,NET_MAY=0,NET_JUN=0,NET_JUL=0,NET_AUG=0,NET_SEP=0,NET_OCT=0,NET_NOV=0,NET_DEC=0,NET_JAN=0,NET_FEB=0,NET_MAR=0," +
"LYNET_APR=" + dr["NET_APR"] + ",LYNET_MAY=" + dr["NET_MAY"] + ",LYNET_JUN=" + dr["NET_JUN"] + ",LYNET_JUL=" + dr["NET_JUL"] + ",LYNET_AUG=" + dr["NET_AUG"] + ",LYNET_SEP=" + dr["NET_SEP"] + ",LYNET_OCT=" + dr["NET_OCT"] + ",LYNET_NOV=" + dr["NET_NOV"] + ",LYNET_DEC=" + dr["NET_DEC"] + ",LYNET_JAN=" + dr["NET_JAN"] + ",LYNET_FEB=" + dr["NET_FEB"] + ",LYNET_MAR=" + dr["NET_MAR"] + "," +
"ADJ_APR=0,ADJ_MAY=0,ADJ_JUN=0,ADJ_JUL=0,ADJ_AUG=0,ADJ_SEP=0,ADJ_OCT=0,ADJ_NOV=0,ADJ_DEC=0,ADJ_JAN=0,ADJ_FEB=0,ADJ_MAR=0," +
"LYADJ_APR=" + dr["ADJ_APR"] + ",LYADJ_MAY=" + dr["ADJ_MAY"] + ",LYADJ_JUN=" + dr["ADJ_JUN"] + ",LYADJ_JUL=" + dr["ADJ_JUL"] + ",LYADJ_AUG=" + dr["ADJ_AUG"] + ",LYADJ_SEP=" + dr["ADJ_SEP"] + ",LYADJ_OCT=" + dr["ADJ_OCT"] + ",LYADJ_NOV=" + dr["ADJ_NOV"] + ",LYADJ_DEC=" + dr["ADJ_DEC"] + ",LYADJ_JAN=" + dr["ADJ_JAN"] + ",LYADJ_FEB=" + dr["ADJ_FEB"] + ",LYADJ_MAR=" + dr["ADJ_MAR"] +
" where CATEGORY=\'" + str + "\'";

da.UpdateCommand = upcom;
upcom.ExecuteNonQuery();

}
dt.AcceptChanges();

dataGridView1.DataSource = dt;
}

DataSet SelectMethod(string tbName)
{
selcom.CommandText = "select * from CON_"+tbName;
selcom.Connection = con;
da.SelectCommand = selcom;
da.Fill(ds);
return ds;

}

private void butSelectLoc_Click(object sender, EventArgs e)
{
DialogResult result = openFileDialog1.ShowDialog();

if (result == DialogResult.OK)
{
string path = openFileDialog1.FileName;
txtSelectLoc.Text = path;
}
}

regards
ruwandi

rkherath

Re: update statement syntax error

Colin Angus Mackay18-Apr-07 22:24

Colin Angus Mackay

18-Apr-07 22:24

Use parameterised queries. DO NOT INJECT DATA INTO A SQL STATEMENT. The security of your application will be compromised. See: SQL Injection Attacks and Tips on How to Prevent Them[^]

Re: update statement syntax error

rkherath18-Apr-07 22:46

rkherath

18-Apr-07 22:46

hi,

thanks. I will do that.

regards
ruwandi

rkherath

show tables

tradakad18-Apr-07 20:35

tradakad

18-Apr-07 20:35

Hi, ALL!
in MySQL I could execute this "show tables" and i got a list of tables in database. can I get a list of tables in a MS SQL database and how?

thanx!

--
"Success is simple. Do what's right, the right way, at the right time."

best regards,
tradakad

Re: show tables

gauthee18-Apr-07 20:55

gauthee

18-Apr-07 20:55

select * from INFORMATION_SCHEMA.TABLES

Gautham

Re: show tables

tradakad18-Apr-07 21:46

tradakad

18-Apr-07 21:46

Yep, i mean exactly this thing..
thank you, bro!

--
"Success is simple. Do what's right, the right way, at the right time."

best regards,
tradakad

Re: show tables

gauthee18-Apr-07 22:47

gauthee

18-Apr-07 22:47

welcome anytime bro!

Gautham

2-way Merge Replication(PDASql Server 2000)

ayyappa4902118-Apr-07 19:41

ayyappa49021

18-Apr-07 19:41

I am working on Windows mobile platform using C#. I am using Merge Replication to do synchronization between SQL Server2000 and SQL Server 2005 Mobile edition and t is working fine.

The Server Tables are copied in the Client DB. It works fine with one way, i.e., server pushing data to Client Database (in PDA), but when i tried to update from PDA database, server keeps over writting PDA databse.

The requirement is that before adding our PDA database as subscriber,there are some tables with same name and structure as in Server with some records. After that i added it as subscriber and sycnchronized.The tables in the server are going to overrite the records in PDA.My requirement is to not overrite the records and it should update the existing table.Is it possible....Can Any one Help meeeeeeeeeeeee plzzzzzzzzzz.

Ayyappa Konakalla

find exact Hour and minutes.....

Member 387988118-Apr-07 19:05

Member 3879881

18-Apr-07 19:05

Hi i want to know exact hour and minute of two times...,
i used this query:
"SELECT '2007-03-14 12:50:55.070' as login,'2007-03-14 13:00:55.070' as logout,DATEDIFF(hour, '2007-03-14 12:50:55.070', '2007-03-14 13:00:55.070') AS hours,DATEDIFF(minute, '2007-03-14 12:50:55.070', '2007-03-14 13:00:55.070') AS minut"

But i am getting value as 1 hour 10 minute like...,
But actual output is 10 minute only...,
And suppose the second time will be in some other day means...,
the logout time will be '2007-03-14 13:00:55.070' as logout
for this also i want to calculate exact hours and minutes like that any query is there in sqlserver???
Advance thanks...

Magi

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