Comparing data from two data tables

Question

I have this code which compares data from two data tables. It does this by using a primary column and inserting the new record from table2 to table1. This loop continues for a large number of tables. I want to optimize it. Kindly give suggestions.

foreach (DataRow drRow in table2.Rows)
{
 if(!table1.Rows.Contains(drRow["KeyId"]))
 {
 table1.ImportRow(drRow);
 }
}

• Purnil Soni: What version of .net framework is being used ?
• rrk: Hi purnil, its 3.5
• Malachi: I think that this might be the best way to do it. I have done a little bit of looking and it seems like the other ways that I have thought about doing it fall short of this code.
• rrk: Malachi, thanks a lot for looking into it. I too trying to find other way which will be more optimized.

Answer 1

For .net framework 3.5, you can have following code improvements:

foreach (var drRow in table2.Rows.Cast<DataRow>()
 .Where(drRow => !table1.Rows.Contains(drRow["KeyId"]))) 
{
 table1.ImportRow(drRow); 
}

1. part of body can be converted to LINQ-expression
2. use "var" (implicitly typed) instead of "DataRow" (explicitly typed)

• rrk: Hi Purnil,I tried and i was not able to see any improvement in performance. In fact the old code was faster. Anyways thanks for your inputs :)