To select one career, click the row selector with the wanted career. To choose numerous industries, hold down the Ctrl secret, and click this new line selector for each and every job.
If you want the transaction of your industries within the a simultaneous-profession primary the answer to change from the transaction ones sphere from the desk, mouse click Spiders to your toolbar showing the brand new Spiders dialogue field, then reorder the field labels to the directory entitled PrimaryKey.
Referential stability
Referential ethics try a system regarding rules you to definitely Availableness uses to ensure that dating anywhere between details into the relevant dining tables try appropriate, and that you do not eventually erase or alter related investigation. You might place referential stability when all the following conditions is actually true:
- The matching community regarding primary desk are a first trick otherwise has actually a special list.
- The new associated sphere have the same study types of. There have been two exceptions. An enthusiastic AutoNumber community might be connected with several occupation that features a good FieldSize possessions means from Much time Integer, and an enthusiastic AutoNumber field that a good FieldSize possessions function from Duplication ID can be regarding several field who has got a great FieldSize assets form regarding Replication ID asiandate.
- Each other tables fall under an equivalent Supply databases. If the tables are connected dining tables, they must be tables during the Access format, while need open the newest databases where they are kept setting referential ethics. Referential integrity cannot be enforced having linked tables out of databases within the almost every other types.
- You simply can’t go into a respect on the overseas secret realm of the latest relevant table that does not can be found however key of one’s first desk. But not, you could potentially enter a great Null worth on the overseas secret. So it determine that ideas are unrelated. Including, you can not have an order which is allotted to a consumer who would maybe not can be found. Yet not, it’s possible to have your order that’s assigned to not one person from the entering a good Null really worth throughout the CustomerID career.
- You can not erase an archive regarding a first desk if the complimentary suggestions exists within the an associated dining table. Such as for example, you can’t delete a worker checklist regarding the “Employees” dining table in the event that there are instructions assigned to the fresh new personnel about “Orders” dining table.
- You can not transform an initial key value throughout the priple, you simply cannot change an employee’s ID on the “Employees” table when the discover orders assigned to one personnel regarding the “Orders” desk.
Streaming condition and you will deletes
To own relationship where referential ethics try enforced, you could potentially specify whether you desire The means to access automatically cascade inform or cascade delete relevant suggestions. For people who set such possibilities, erase and update businesses that would constantly be prevented by the referential stability statutes is actually permitted. After you remove information or change number 1 key philosophy during the a top dining table, Supply helps to make the requisite change to help you relevant dining tables in preserving referential ethics.
If you click to choose the Cascade Change Related Industries evaluate field when you explain a love, when that you replace the first key out-of an archive in the primary desk, Microsoft Access immediately standing the key the answer to brand new value throughout associated ideas. Instance, for individuals who transform a customer’s ID on the “Customers” dining table, brand new CustomerID occupation on the “Orders” desk try instantly upgraded each certainly one of one to owner’s instructions therefore the matchmaking isn’t broken. Availability cascades status instead showing one content.
If the first type in an important desk was an AutoNumber profession, deciding on the Cascade Revision Relevant Areas take a look at package doesn’t have perception because you you should never replace the worthy of inside a keen AutoNumber occupation.