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Since they are optional, they could be 'missing' if in a linked table. That is, you would simply not add the linked row until there was some data to supply. This would conserve space in the database (but would complicate your application design a bit, since you would need to deal with returning no rows for the join). It would also simplify tasks like locating which employees had no skillsets, etc.
If you keep this in the main table, every row will have the colums, which take up some space even if NULL.
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The key advantage that separating the skillset information out to an Employee_Skillset table is that you could store much more information, make it easier to retrieve and have greater control over the data entry. You could have columns to cover not just the skill but the level and any qualifications held. It is perfectly possible to store and retrieve this data from free-text columns but you have a greater chance of simple things like spelling mistakes causing incorrect query results.
Ian
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i have no idea about using a SQL database but i need it in my application.
any help 
salie
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If you don't know anything about it, how can you know you need it?
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coz it is one of the requirements of the project c want i mean 
salie
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Is there any way in sql reporting services to let the end-user change the field that is being sorted and how it is sorted (ASC/DESC)?
-GK
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I'm having a problem connecting to the Sql Server database setup on my local machine. I can connect to my company's network database with no problem so it has to be something wrong with my connection string.
I'm using Sql Server 2005.
Here's the current string I'm using in my web.config file:
----------------------------------------------------------------
<add name="DBConn"
connectionString="Server=(local);Initial Catalog = <my database name>;User Id =<the username I log in with>;Password=<I don't login with a password so I left this property blank>"
providerName="System.Data.SqlClient"/>
-----------------------------------------------------------------
Where can I locate the necessary data for each of these properties? I'm pretty sure the "Server" property is correct however the rest is a pure guess.
Please help. I can't progress until I'm able to connect to my database.
Thanks in advance.
-Goalie35
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I think you need to do some reading on connection strings
Goalie35 wrote:
User Id =<the username I log in with>
It may not be the name you log in with
Goalie35 wrote:
Password=<I don't login with a password so I left this property blank>"
You need to specify a password
only two letters away from being an asset
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How about removing the user/password and use Trusted_Connection=true;
see http://www.connectionstrings.com for more info.
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Thanks for the help guys.
Smallguy78, the Trusted_Connection=True worked.
Thanks.
-Goalie35
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The trusted_connection=true relates to your windows userid and passward. The user_id and password relate to SQL Server login information.
Ian
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i am using microsoft access to view SQL.I need help on how to set a column to currency [this column result after multiplying the number of units bought(UNIT_BOUGHT) and the unit price(UNIT_PRICE)(unit price is in currency)].So the results are named SUBTOTAL,i want them to contain currency.
LudereMP
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Are you suing MS Access as a front-end to a SQL back-end database?
If so, you can set the column type to 'Currency' in the table designer.
Steve
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I have the following tables
Person
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Id
Name
Locations
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Id
Name
PersonLocation
---------------
Id
PersonId
LocationId
So each person can be in multiple locations.
The problem with the 3rd table is with a lots of Locations, this table can grow huge (2million+ rows). Even with indexes on PersonId and LocationId, I'm thinking this will make inserts take a lot longer once the table is big. Is this the optimum way of storing the relationship between the two tables? Or there a clevered way of doing the storage?
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Welcome to the wonderfull world of relational databases!
This is the most efficient, and the most sensible, way to store this information. Whilst 2 million records may seem a lot, it really isn't. Inserting and deleting will not be noticably slower when the table has many rows than when the table has few rows in it.
The alternative to this structure would be to use a denormalised table that has the person_name and location_name stored. Not only does this arrangement require more storage space, but what happens if:
1. You need to change the name of a location or person?
2. Two or more people have the same name?
BTW, you only need a single non-clustered index on the personid and locationid fields as I assume that the combination would be unique.
Ian
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Yes the combination will be unique so a clustered index would work.
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A clustered index in this case may not be useful unless your searches will always be on one column such as Person_id. A clustered index over the two columns will be no advantage in this case as the combinations are unique. Having a clustered index on a table may mave an impact on performance as it involves a physical re-ordering of data every time that a change is made. In this case you will still need a non-clustered unique index covering both person_id and location_id to ensure uniqueness of combinations.
Ian
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Hi everyone,
I don't have any previous knowledge of SQL but need to be able to retrieve data from an SQL database here at work. From what I've managed to gather from some sample code for running SQL commands on an Excel file but the code doesn't work against an sql server. I've searched high and low on the net and best I have managed is to be able to connect to the database successfully...
Try<br />
CN.ConnectionString = _<br />
"Network Library=DBMSSOCN;" & _<br />
"Data Source=xxx.xxx.xxx.xxx,xxxx;" & _<br />
"Initial Catalog=" & dbName & ";" & _<br />
"User ID=" & dbUser & ";" & _<br />
"Password=" & dbPass<br />
CN.Open()<br />
Catch ex As Exception<br />
Console.WriteLine(ex.Message)<br />
End Try
But I don't know what to do next as far as retrieving the actual data 
Is anyone able to help?
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Hi,
create a data adapter or data reader or command object as
Dim dap as new sqldataadapter()
and then write an Sql Statement in the braces to retrieve the data.Like
Select * from (Table_name) where empno= eno or anything according to the query.ok
srushti08
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I'm doing a program to try to learn some ADO.NET programming and I'm running into the following problem:
One of the fields in my database is a VarBinary(MAX) that I want to store and image in.
I created my own SqlDataAdapter to talk to the DataSet and such, now on the SqlDataAdapter for the InsertCommand and UpdateCommand I have the following parameter to correspond to the image field in the database:
param_arr2[7] = new SqlParameter ("@jacket", SqlDbType.Image, 15000, "jacket");the problem is that I don't know how big the image is going to be so I don't want to have to specify the size in the parameter, and if I change the parameter to
param_arr2[7] = new SqlParameter ("@jacket", SqlDbType.Image);when I try to update the data I get and exception with the message "Parameterized Query ... expects parameter @jacket, which was not supplied." Any help on this problem would be most appreciated.
Thanks!
- Aaron
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Image and VarBinary are two different column types. You should use SqlDbType.VarBinary if that is what is defined in the DB structure.
Image: Stored out of band (not on the same page as the other table data) and can be up to 2 gigs in size.
VarBinary: Stored with the other table data and limited by page size ~8000 bytes give or take your other columns.
Not sure if these descriptions changed with 2005.
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According to the SQL Server 2005 BOL the image datatype is going to be removed in future versions of SQL Server, which is why I in the database I set the field type to varbinary(max), which indicates maximum storage is 2^31-1 bytes. The same problem still occurs in the program if I run it using
param_arr2[7] = new SqlParameter ("@jacket", SqlDbType.VarBinary);I still get the same exception "Parameterized Query ... expects parameter @jacket, which was not supplied."
Is there any way to set this up to have to parameter use as much space as is necessary to store the image?
Thanks for the help.
- Aaron
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Quoting from MSDN:
"For variable-length data types, Size describes the maximum amount of data to transmit to the server. For example, for a Unicode string value, Size could be used to limit the amount of data sent to the server to the first one hundred characters."
So, you should set the size to the largest expected size you can handle.
For updates, set the size later (just before using it in the sqlCommand):
((SqlParameter)param_array[7]).size = mydata.length;
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