Database

declare @a varchar(max)

select @a = replicate('a',7999) + 'b'
print @a

--prints 7999 a's and a b

select @a = replicate('x',8000) + 't'
print @a

--prints 8000 x's but no t

select count(occupants) from tablename<br />
group by [datecol],roomtype<br />
having datecol between '2008-05-01' and '2008-05-31'

insert into [Table] (Field) Values (0x1232132132)

<br />
CREATE PROCEDURE myProc<br />
  @param1 INT = NULL<br />
  @param2 VARCHAR(50) = NULL<br />
AS<br />
  SELECT * FROM [sometable] WHERE col1= COALESCE(@param1, col1) AND col2 = COALESCE(@param2, col2)<br />
GO<br />

<br />
public class DataLayer {<br />
  public DataSet GetSomeData(int param1, string param2){<br />
    DataSet myData = new DataSet();<br />
<br />
    using(DbConnection conn = GetConnectionFactoryMethod()){<br />
      using(DbCommand cmd = new DbCommand(conn, "SELECT .... FROM .... WHERE col1 = @param1 AND col2 = @param2")){<br />
         cmd.Parameters.Add("@param1", .....);<br />
         cmd.Parameters.Add("@param2", .....);<br />
<br />
         cmd.Parameters["@param1"].Value = param1;<br />
         cmd.Parameters["@param2"].Value = param2;<br />
<br />
         DbDataAdapter da = new DbDataAdapter(cmd);<br />
         da.Fill(myData);<br />
      }<br />
    }<br />
<br />
    return myData;<br />
  }<br />
<br />
  public DataSet GetSomeDifferentData(string param1, bool param2){<br />
    // ...... implementation .....<br />
  }<br />
<br />
  private DbConnection GetConnectionFactoryMethod(){<br />
    return new SqlConnection("... connection string ...");<br />
  }<br />
}<br />

<br />
  DataLayer myDataLayer = new DataLayer();<br />
<br />
  DataSet myData = myDataLayer.GetSomeData(5, "my string");<br />
  DataSet myData2 = myDataLayer.GetSomeDifferentData("some value", true);<br />
<br />

MozhdehQeraati wrote:

if I want to take for example an exclusive lock at a row-level.