Updating data between FileMaker and ODBC data sources
In general, committing data in ODBC data sources works the same as committing FileMaker data. For example, FileMaker saves changes to external data when you exit a field or move to another record. For more information, see Committing data in records. However, because external data is controlled by different software and can be used interactively by users working outside of FileMaker software, there are certain actions you can take to assure you have the latest record data and table schema.
To display the latest data from an ODBC data source:
In Browse mode, choose Records menu > Refresh Window.
Current data, including data entered by users outside of FileMaker, appears. You can also flush the internal cache with the Refresh Window script step.
For ODBC tables, FileMaker uses “optimistic locking” to control data entry. FileMaker does not automatically refresh data when you begin entering data in an external record or when you do a Find on ODBC data.
To synchronize field schema between FileMaker and the ODBC data source:
Choose File menu > Manage > Database.
FileMaker displays fields from the ODBC table. The field names appear in italics.
FileMaker updates the schema between the ODBC source and the “shadow” table. You have not changed the field schema in the data source, only updated FileMaker’s table schema for any new or missing fields. For example, if you delete a field from an ODBC table in the relationships graph, when you click Sync again, the field from the external data source will reappear.
Note After you synchronize, any field options you set in FileMaker Pro might be reset if the ODBC data source doesn’t force that option. For example, if you selected the Not empty validation option, after synchronizing, you might have to reset that option.
Related topics 
Restoring links to ODBC data sources