Checking the integrity of the links

Use the Link Integrity Check wizard to check the integrity of the link records for a database, that is, whether the data held for links is consistent with that held for the entity records at the ends of the links. You should check the integrity of the database schema before you check link integrity.

About this task

The Link Integrity Check wizard reports any problems found with links or the entities they reference and offers to fix those that it can repair. Most repairs are safe and non-destructive, but some repairs might involve removing invalid data. You see a list of proposed repairs and you can abandon repairs so that you can inspect suspect data and perhaps recover it by other means. After repair, you should look at places where the wizard has added entities and links, possibly with blank mandatory fields, and decide how to make these records usable. Eventually, you must repair problems to avoid the possibility of misleading analysis based on faulty data.

Procedure

To use the Link Integrity Check wizard:

Log on to the relevant security file as a database administrator but do not open the database.
In iBase Designer, select Tools > Database Administration > Link Integrity Check.
Select a database from the list and click Next.

Any links where there are problems in one of two required link records are displayed. In a properly functioning database, the list should be empty in this and all following pages. Click Next to display the next page if there are no errors reported:


Page	Possible repair
Links with missing attribute information	If there are errors, turn on the check box for each attribute error that you want the wizard to repair with blank data, which is the only possible repair.
Links missing both of two required link records	If there are errors, turn on the check box for each link that you want the wizard to delete, which is the only possible repair.
Links using end entity records where the entity record is missing	If there are problems, turn on the check box for each entity that you want the wizard to create with blank data, which is the only possible repair.
Links appearing to use more than the two end entity records, which is not meaningful	You must make a note of these links and fix the problem by other means.

A list of any repairs that you have requested in previous steps is displayed. Click:
- Cancel To abandon all repairs.
- BackIf you want to select a different set of repairs in earlier pages of the wizard.
- FinishTo perform the listed repairs.
Click Close. The database is opened, whether or not you asked for any repairs.What you do next depends on whether you repaired errors:
- If the wizard did not report errors, the database is ready for use.
- If the wizard reported errors and you chose to repair them, close the database and run the wizard again. (Some errors are only revealed after the wizard has made its first repairs.)
Run the wizard again until you see no errors. After two uses with repairs performed, the third use of the wizard should always be error free.

What to do next

After repairs, you might need to add data for any records that are created with blank data fields or to replace removed entities or links, perhaps by importing data from a suitable source.