Creating a solution > About setting up container fields > Setting up container fields to store data externally
Setting up container fields to store data externally
When you create a container field, data is by default embedded in the field.
You can set up a container field to store data externally. Data that’s stored externally is by default encrypted, using secure storage, and can only be read by the FileMaker Pro application. FileMaker Pro manages the encrypted files automatically. However, you can use the open storage option, which removes encryption and keeps the files in their native formats.
You can set up different storage options (embedded or stored externally) for individual container fields in a database. Also, you can store container data externally in different folders on the file system.
To set up external storage:
1. Choose File menu > Manage > Database.
2. Click the Fields tab.
3. If your database contains more than one table, select the appropriate table from the Table list.
4. Select an existing field or define a new one.
5. Click Options (or double-click the field name).
6. In the Options for Field dialog box, click the Storage tab.
7. In the Container area, select Store container data externally.
8. For relative to, choose a base directory from the list.
You can store container data in a different directory. See Managing external storage of container data.
9. Choose how you want the container data stored.
Secure Storage (the default)
Encrypt the data, making it readable by FileMaker Pro using secure storage. FileMaker Pro creates a subdirectory named "Secure" in the base directory and randomly distributes the files across subdirectories, and creates new subdirectories as needed.
Open Storage
Allow container files to stay in their original format and control where the files are stored. The default path is relative to the base directory and is in the format table/field.
You can type a different path or click Specify to specify a calculation.
10. Click OK.
If the database contains one table, then the database in the base directory path and the table in the default open storage path will have the same name. For example, "Properties" in the base directory [database location]/Properties is the database filename, and "Properties" in the open storage path Properties/Photo is the table name.
To move existing data that’s embedded in container fields, you must manually transfer the data. See Transferring container data.
If you specify a calculation for a container field that uses open storage:
If a filename that results from a calculation is not unique, FileMaker Pro appends the duplicate filename with a sequential number (for example, Invoice_1.txt).
Design the calculation to reduce the number of stored duplicate filenames. For example, if you design a Candidates recruitment database and you expect that most records will contain a file named Resume.doc, you can specify the following calculation for open storage: "Candidates/" & CandidateID.
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