A question about accessing a database using ado.net

[tony]

Hello!

This method below works but how can it work when I don't have any open on
myOleDbConnecti on ?
As I have understood this is that there must exist an myOleDbConnecti on
..Open(); in my case
but it works just as good with one as without one.
public ArrayList GetAllPostNames ()
{
// here I get the connection from a singleton in a class library dll
OleDbConnection myOleDbConnecti on =
MeltPracStorage .instance.utcas MspDbConnection ;
DataSet dataSet = new DataSet();
ArrayList arrayList = new ArrayList();

OleDbDataAdapte r myOleDbAdapter = new OleDbDataAdapte r("select * "
+
"from MSP_COMP t1 " +
"where ACTIVE = 1 and " +
"SAVE_TIME = " +
"(select max(SAVE_TIME) " +
"from MSP_COMP " +
"where COMP_NAME = t1.COMP_NAME)
order by COMP_NAME", myOleDbConnecti on);

myOleDbAdapter. Fill( dataSet );

//loop through the dataset and add each COMP_NAME result to the
ArrayList and return it
foreach( DataRow row in dataSet.Tables[0].Rows)
arrayList.Add( row["COMP_NAME"] );

return arrayList;
}

//Tony

[Morten Wennevik]

Hi Tony,

DataAdapter.Fil l works in two ways.

1) If there is an open connection, this connection is used, and the connection is left untouched
2) If no connection is found. Connection.Open is called, and Connection.Clos e is called after Fill

On Fri, 18 Aug 2006 13:32:22 +0200, tony <jo************ *****@telia.com >wrote:

Hello!

This method below works but how can it work when I don't have any openon
myOleDbConnecti on ?
As I have understood this is that there must exist an myOleDbConnecti on
.Open(); in my case
but it works just as good with one as without one.
public ArrayList GetAllPostNames ()
{
// here I get the connection from a singleton in a class library dll
OleDbConnection myOleDbConnecti on =
MeltPracStorage .instance.utcas MspDbConnection ;
DataSet dataSet = new DataSet();
ArrayList arrayList = new ArrayList();

OleDbDataAdapte r myOleDbAdapter = new OleDbDataAdapte r("select * "
+
"from MSP_COMP t1 " +
"where ACTIVE = 1 and " +
"SAVE_TIME = " +
"(select max(SAVE_TIME) " +
"from MSP_COMP " +
"where COMP_NAME = t1.COMP_NAME)
order by COMP_NAME", myOleDbConnecti on);

myOleDbAdapter. Fill( dataSet );

//loop through the dataset and add each COMP_NAME result to the
ArrayList and return it
foreach( DataRow row in dataSet.Tables[0].Rows)
arrayList.Add( row["COMP_NAME"] );

return arrayList;
}

//Tony

--
Happy coding!
Morten Wennevik [C# MVP]

[tony]

Hello!!

Do you recomment that a close should be used in my case or can I just leave
it as my method below is now.

//Tony
"Morten Wennevik" <Mo************ @hotmail.comskr ev i meddelandet
news:op.teg89bx aklbvpo@stone.. .
Hi Tony,

DataAdapter.Fil l works in two ways.

1) If there is an open connection, this connection is used, and the
connection is left untouched
2) If no connection is found. Connection.Open is called, and
Connection.Clos e is called after Fill

On Fri, 18 Aug 2006 13:32:22 +0200, tony <jo************ *****@telia.com >
wrote:

Hello!

This method below works but how can it work when I don't have any open on
myOleDbConnecti on ?
As I have understood this is that there must exist an myOleDbConnecti on
.Open(); in my case
but it works just as good with one as without one.
public ArrayList GetAllPostNames ()
{
// here I get the connection from a singleton in a class library

dll

OleDbConnection myOleDbConnecti on =
MeltPracStorage .instance.utcas MspDbConnection ;
DataSet dataSet = new DataSet();
ArrayList arrayList = new ArrayList();

OleDbDataAdapte r myOleDbAdapter = new OleDbDataAdapte r("select *

"

+
"from MSP_COMP t1 " +
"where ACTIVE = 1 and " +
"SAVE_TIME = " +
"(select max(SAVE_TIME) " +
"from MSP_COMP " +
"where COMP_NAME =

t1.COMP_NAME)

order by COMP_NAME", myOleDbConnecti on);

myOleDbAdapter. Fill( dataSet );

//loop through the dataset and add each COMP_NAME result to the
ArrayList and return it
foreach( DataRow row in dataSet.Tables[0].Rows)
arrayList.Add( row["COMP_NAME"] );

return arrayList;
}

//Tony

--
Happy coding!
Morten Wennevik [C# MVP]

[Morten Wennevik]

You can leave it as it is

On Fri, 18 Aug 2006 13:57:11 +0200, tony <jo************ *****@telia.com >wrote:

Hello!!

Do you recomment that a close should be used in my case or can I just leave
it as my method below is now.

//Tony
"Morten Wennevik" <Mo************ @hotmail.comskr ev i meddelandet
news:op.teg89bx aklbvpo@stone.. .
Hi Tony,

DataAdapter.Fil l works in two ways.

1) If there is an open connection, this connection is used, and the
connection is left untouched
2) If no connection is found. Connection.Open is called, and
Connection.Clos e is called after Fill

On Fri, 18 Aug 2006 13:32:22 +0200, tony <jo************ *****@telia.com >
wrote:

>Hello!

This method below works but how can it work when I don't have any open on
myOleDbConnect ion ?
As I have understood this is that there must exist an myOleDbConnecti on
.Open(); in my case
but it works just as good with one as without one.
public ArrayList GetAllPostNames ()
{
// here I get the connection from a singleton in a class library

dll

> OleDbConnection myOleDbConnecti on =
MeltPracStorag e.instance.utca sMspDbConnectio n;
DataSet dataSet = new DataSet();
ArrayList arrayList = new ArrayList();

OleDbDataAdapte r myOleDbAdapter = new OleDbDataAdapte r("select *

"

>+
"from MSP_COMP t1 " +
"where ACTIVE = 1 and " +
"SAVE_TIME = " +
"(select max(SAVE_TIME) " +
"from MSP_COMP " +
"where COMP_NAME =

t1.COMP_NAME)

>order by COMP_NAME", myOleDbConnecti on);

myOleDbAdapter. Fill( dataSet );

//loop through the dataset and add each COMP_NAME result to the
ArrayList and return it
foreach( DataRow row in dataSet.Tables[0].Rows)
arrayList.Add( row["COMP_NAME"] );

return arrayList;
}

//Tony

--
Happy coding!
Morten Wennevik [C# MVP]

--
Happy coding!
Morten Wennevik [C# MVP]