Get the career otherwise sphere that you like to define once the the primary secret

To choose you to career, click the row selector to the desired industry. To pick multiple sphere, hold down the newest Ctrl key, and click the line selector each occupation.

If you want the order of the areas in the a parallel-profession no. 1 the answer to change from your order of them areas in the desk, click Spiders for the toolbar to demonstrate new Spiders dialogue field, and then reorder the field names on the index entitled PrimaryKey.

Referential integrity

Referential stability try a network off legislation you to definitely Supply spends to guarantee that dating anywhere between facts in the associated tables are good, and you do not eventually remove or change relevant investigation. You could put referential integrity whenever the adopting the requirements are true:

  • The brand new matching job about no. 1 table is actually a first trick or possess another type of index.
  • New associated fields have a similar study sort of. There have been two exclusions. An AutoNumber occupation should be pertaining to a number community one provides good FieldSize property function out-of A lot of time Integer, and an enthusiastic AutoNumber occupation who has got a beneficial FieldSize possessions form out of Replication ID will likely be connected with several job who’s an effective FieldSize assets function out-of Duplication ID.
  • One another dining tables belong to a comparable Supply database. In case the dining tables are linked tables, they must be tables during the Access style, while need discover the fresh database in which he or she is held to create referential stability. Referential stability can’t be implemented getting linked tables of databases inside most other platforms.
  • You simply cannot enter a value in the foreign key field of the associated table that will not are present in the primary trick of the primary desk. not, you could potentially go into an effective Null really worth regarding overseas secret. That it determine that the records is not related. Such, you cannot have your order that’s assigned to a consumer who does maybe not exists. not, you can get an order that is allotted to nobody of the entering an effective Null worthy of throughout the CustomerID industry.
  • You can’t remove an archive out-of a primary desk in the event that matching records exist during the a connected dining table. Like, you cannot delete an employee number regarding the “Employees” desk in the event that there are commands allotted to the fresh worker on the “Orders” dining table.
  • You simply cannot transform a primary key worthy of regarding the priple, you simply cannot transform an enthusiastic employee’s ID from the “Employees” table when the you can find requests assigned to that worker on “Orders” desk.

Flowing status and deletes

To possess relationship in which referential stability are enforced, you might establish whether you desire Entry to immediately cascade up-date or cascade delete related ideas. For individuals who place these solutions, remove and update businesses that would always be avoided of the referential stability rules was enabled. Once you remove information otherwise transform number 1 trick opinions when you look at the a no. 1 desk, Supply helps make the required changes in order to related tables to preserve referential stability.

For people who click to search for the Cascade Posting Associated Sphere see box once you explain a relationship, any moment which you change the primary key of an archive in the main dining table, Microsoft Availableness instantly position an important the answer to brand new value in all related info. Including, for people who transform a consumer’s ID on the “Customers” dining table, the fresh new CustomerID industry about “Orders” table is actually immediately updated each one of that user’s purchases therefore the relationships isn’t busted. Availableness cascades condition in the place of exhibiting one content.

If the top key in the primary dining table try a keen AutoNumber profession, selecting the Cascade Up-date Related Industries examine field does not have any feeling as you cannot alter the value from inside the an AutoNumber field.