Avatar of Sandiya
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Urgent :compare two datatables

Hi All,

I want a vb.net code tocheck all columns of Source table and see if they exist in Target table. If they dont exist then i want to add the columns in the target table.The source table comes from salesforce and the target table is in sql server.

I just want a code to identify the missing columns and suggest the user to create the column in the target.
.NET ProgrammingASP.NETVisual Basic.NET

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Last Comment

8/22/2022 - Mon
Kamal Khaleefa


i recommend the following

dim dt1 as new datattable=get data from course in db1
dim dt2 as new datattable=get data from course in db2

then write a for loop to compare the columns name
ex: for i as integer=0 to dt1. Columns.Count -1 ...
and then u can know what is the missing
and base on that create a sql statement to do the necessary modification and execute it


Can u please explain the logic to compare column names between 2 datatable

Dirk Haest

You can use linq. Small example attached.

The last query will tell you that you have a column (namely state) in your second datatable that is not in your first datatable

 Private Sub compareTables()
        Dim Table1 As DataTable = New DataTable("Customers")
        Table1.Columns.Add("Name", Type.GetType("System.String"))
        Table1.Columns.Add("Firstname", Type.GetType("System.String"))
        Table1.Columns.Add("Street", Type.GetType("System.String"))
        Table1.Columns.Add("HouseNumber", Type.GetType("System.String"))
        Table1.Columns.Add("PostalCode", Type.GetType("System.String"))

        Dim Table2 As DataTable = New DataTable("Customers2")
        Table2.Columns.Add("Name", Type.GetType("System.String"))
        Table2.Columns.Add("Firstname", Type.GetType("System.String"))
        Table2.Columns.Add("State", Type.GetType("System.String"))

        Dim firstquery = From col In Table1.Columns Select col.columnName
        Dim notinsecondtable = From col In Table2.Columns Where Not firstquery.Contains(col.columnName)
    End Sub

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Sorry i have not used linq can u please explain me in detail how to proceed after the code
Nasir Razzaq


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Thanks all
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