When you create a mapping, you must add one or more source definitions to it. When you drag a source into the Mapping Designer workspace, you add an instance of the source definition to the mapping.

For relational sources, you can edit the source definition and override the default source table name.

Every mapping requires at least one of the following source qualifiers that determines how the Integration Service reads the source data:

You can let the Designer create the source qualifier by default. Each time you drag a source instance into a mapping, the Designer adds a source qualifier and connects it to the source. Use the automatic source qualifier creation when you want to create one source qualifier for each source in the mapping. You can disable the automatic creation when you want to join data from different relational sources. You can then manually create and connect it to the source.

When you edit the source in the Source Analyzer, all instances of the source in mappings inherit the changes. Some changes might invalidate the mappings using the source.

However, you specify some properties for every source instance in a mapping. Double-click the source instance in the Mapping Designer and click the Properties tab. For relational sources, you can specify the table owner name. For flat file sources, you can specify the default datetime format, thousands separator, and decimal separator.