March, 2010

Data comparison is a difficult and resource-intensive process. For convenience, this process can be divided into several steps.
First, you should compare tables from one database on one server with the database on the other server. You should choose columns for data comparison, and also choose a column that will be a comparison key.
The next step is to choose all data from these tables or some specified part of the data.
The third and the most important step is comparison of the two tables by the selected comparison key itself. During this process the status of each record is set to “only in source”, “only in target”, “different”, or “equal”.
The final steps of the data comparison process are including records to the synchronization and synchronization itself. During these steps records needed for synchronization are chosen, update script is created, and after that the script is executed.
You can read a detailed description of the comparison process here.

Now let’s look at the third step (data comparison) thoroughly.

There are several ways of data comparison that differ only by the side where data comparison is going to be performed – on the server side or on the client PC.

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