How to compare 2 dataTables
I have 2 datatables and I just want to know if they are the same or not. By "the same", I mean do they have exactly the same number of rows with exactly the same data in each column, or not. I'd love to write (find) a method which accepts both tables and returns a boolean.
How can I compare 2 datatables in this way? Both have identical schemas.
public static bool AreTablesTheSame( DataTable tbl1, DataTable tbl2)
{
if (tbl1.Rows.Count != tbl2.Rows.Count || tbl1.Columns.Count != tbl2.Columns.Count)
return false;
for ( int i = 0; i < tbl1.Rows.Count; i++)
{
for ( int c = 0; c < tbl1.Columns.Count; c++)
{
if (!Equals(tbl1.Rows[i][c] ,tbl2.Rows[i][c]))
return false;
}
}
return true;
}
If you were returning a DataTable as a function you could:
DataTable dataTable1; // Load with data
DataTable dataTable2; // Load with data (same schema)
// Fast check for row count equality.
if ( dataTable1.Rows.Count != dataTable2.Rows.Count) {
return true;
}
var differences =
dataTable1.AsEnumerable().Except(dataTable2.AsEnumerable(),
DataRowComparer.Default);
return differences.Any() ? differences.CopyToDataTable() : new DataTable();
You would need to loop through the rows of each table, and then through each column within that loop to compare individual values.
There's a code sample here: http://canlu.blogspot.com/2009/05/how-to-compare-two-datatables-in-adonet.html
The OP, MAW74656, originally posted this answer in the question body in response to the accepted answer, as explained in this comment:
I used this and wrote a public method to call the code and return the boolean.
The OP's answer:
Code Used:
public bool tablesAreTheSame(DataTable table1, DataTable table2) { DataTable dt; dt = getDifferentRecords(table1, table2); if (dt.Rows.Count == 0) return true; else return false; } //Found at http://canlu.blogspot.com/2009/05/how-to-compare-two-datatables-in-adonet.html private DataTable getDifferentRecords(DataTable FirstDataTable, DataTable SecondDataTable) { //Create Empty Table DataTable ResultDataTable = new DataTable("ResultDataTable"); //use a Dataset to make use of a DataRelation object using (DataSet ds = new DataSet()) { //Add tables ds.Tables.AddRange(new DataTable[] { FirstDataTable.Copy(), SecondDataTable.Copy() }); //Get Columns for DataRelation DataColumn[] firstColumns = new DataColumn[ds.Tables[0].Columns.Count]; for (int i = 0; i < firstColumns.Length; i++) { firstColumns[i] = ds.Tables[0].Columns[i]; } DataColumn[] secondColumns = new DataColumn[ds.Tables[1].Columns.Count]; for (int i = 0; i < secondColumns.Length; i++) { secondColumns[i] = ds.Tables[1].Columns[i]; } //Create DataRelation DataRelation r1 = new DataRelation(string.Empty, firstColumns, secondColumns, false); ds.Relations.Add(r1); DataRelation r2 = new DataRelation(string.Empty, secondColumns, firstColumns, false); ds.Relations.Add(r2); //Create columns for return table for (int i = 0; i < FirstDataTable.Columns.Count; i++) { ResultDataTable.Columns.Add(FirstDataTable.Columns[i].ColumnName, FirstDataTable.Columns[i].DataType); } //If FirstDataTable Row not in SecondDataTable, Add to ResultDataTable. ResultDataTable.BeginLoadData(); foreach (DataRow parentrow in ds.Tables[0].Rows) { DataRow[] childrows = parentrow.GetChildRows(r1); if (childrows == null || childrows.Length == 0) ResultDataTable.LoadDataRow(parentrow.ItemArray, true); } //If SecondDataTable Row not in FirstDataTable, Add to ResultDataTable. foreach (DataRow parentrow in ds.Tables[1].Rows) { DataRow[] childrows = parentrow.GetChildRows(r2); if (childrows == null || childrows.Length == 0) ResultDataTable.LoadDataRow(parentrow.ItemArray, true); } ResultDataTable.EndLoadData(); } return ResultDataTable; }
Try to make use of linq to Dataset
(from b in table1.AsEnumerable()
select new { id = b.Field<int>("id")}).Except(
from a in table2.AsEnumerable()
select new {id = a.Field<int>("id")})
Check this article : Comparing DataSets using LINQ