SQL Management Studio 2012 with Excel vba connection string set up - sql

Question

I would like to set up a vba code that would connect to sql management studio 2012 a run the query, which I would specify in the vba code. I have read every similar question here on stack overflow but when I try to replicate them, I always get an error, ussualy that the login failed for user.
I think I am setting up the string connection wrong. Also, I would need the user authentication by Windows authentication.
I know the database name, server name and my user name.
This is the code I am using and which is giving me an error.
Sub ConnectionExample6()
Dim cnn As ADODB.Connection
Dim rs As ADODB.Recordset
Set cnn = New ADODB.Connection
' Open a connection by referencing the ODBC driver.
cnn.ConnectionString = "driver={SQL Server};" & _
"server=SERVER NAME;uid=USER ID;pwd=MyPassword;database=DATABASE NAME"
cnn.Open
' Create a Recordset by executing an SQL statement.
Set rs = cnn.Execute("Select top 100 * from "TABLE NAME" aac " & _
"where aac.EffectiveDate = '10/04/16'")
' Close the connection.
rs.Close
End Sub
Can someone walk me through the connection string and how to set it up step by step? Thank you.

Answer 1

Authentication
If you're connecting to SQL Server, you should prefer Windows Authentication if that's available: you create a Login at server level for a group of Active Directory users, and then you create a Windows-Authenticated User in your database using that login.
That way you are keeping passwords and usernames out of hard-coded strings, and let the network deal with authentication.
Assuming you don't want to be maintaining passwords in dozens of copies of macro-enabled workbooks across your network, you'll want to use Windows Authentication.
Integrated Security=SSPI; Persist Security Info=True;
Server
Connection strings are annoying - seems there's a different format/wording for every single different thing that's able to parse them!
Since you're using ADODB, you'll want to specify a Provider, a Data Source and, optionally, an Initial Catalog:
Provider=SQLOLEDB.1; Data Source=SQL Server instance name; Initial Catalog=Database name;
Who?
Each connection can be monitored on the server; when building your connection string you can optionally specify a Workstation ID to identify the machine the connection is for.
Workstation ID=computer name;
You can get the computer name by fetching the environment variable value, using Environ$:
Private Function GetWorkstationId() As String
GetWorkstationId = Environ$("ComputerName")
End Function
Given a SQL Server instance named SomeSqlServer, a database named SomeDatabase, and using Windows Authentication, the ADODB connection string would look like this:
Dim connString As String
connString = "Provider=SQLOLEDB.1; Data Source=SomeSqlServer; Initial Catalog=SomeDatabase; Integrated Security=SSPI; Persist Security Info=True;"
Given SQL Authentication (with a hard-coded user name and password) for SomeUser with SomePassword:
connString = "Provider=SQLOLEDB.1; Data Source=SomeSqlServer; Initial Catalog=SomeDatabase; UID=SomeUser; PWD=SomePassword;"
Commands
You don't want to be concatenating arbitrary user input into a WHERE clause; avoid executing an SQL string directly from the ADODB.Connection object.
Instead, create an ADODB.Command, and parameterize your query.
Dim sql As String
sql = "SELECT Foo, Bar FROM dbo.FooBars WHERE Foo = ? AND DateInserted > ?"
Here we have 2 parameters.
First we create the command:
Dim cmd As ADODB.Command
Set cmd = New ADODB.Command
cmd.ActiveConnection = conn
cmd.CommandType = adCmdText
cmd.CommandText = sql
Then its parameters, assuming we have their respective values in param1Value and param2Value local variables:
Dim param1 As ADODB.Parameter ' a string parameter
Set param1 = New ADODB.Parameter
param1.Type = adVarWChar
param1.Direction = adParamInput
param1.Size = Len(param1Value)
param1.Value = param1Value
cmd.Parameters.Append param1
Dim param2 As ADODB.Parameter ' a date parameter
Set param2 = New ADODB.Parameter
param2.Type = adDate
param2.Direction = adParamInput
param2.Value = param2Value
cmd.Parameters.Append param2
Then we retrieve the recordset by executing the command:
Dim results As ADODB.Recordset
Set results = cmd.Execute
Of course this looks very verbose, but it can easily be refactored into functions dedicated to creating a parameter given a value of a certain type.
As a result, you avoid this situation, because you're no longer executing arbitrary user input concatenated into a query: