O'Reilly logo

Applying and Extending Oracle Spatial by Siva Ravada, Simon Gerard Greener

Stay ahead with the world's most comprehensive technology and business learning platform.

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, tutorials, and more.

Start Free Trial

No credit card required

Constraints with asynchronous triggers

Asynchronous triggers can be implemented in different ways, and one common practice is to use a queue. A queue is used to detect changes in the tables, and then based on the base table, specific checks can be done. As we are introducing a new concept of queues here, we will keep the spatial constraint part simple and do the validation checks using an asynchronous trigger.

Oracle provides PL/SQL procedures in the DBMS_AQ package for creating and using queues. In our example, a simple queue is used to insert information about new rows of data coming into the LAND_PARCELS table. Then, an asynchronous process can take entries out of the queue and process them one at a time.

Creating a queue

We first create a type ...

With Safari, you learn the way you learn best. Get unlimited access to videos, live online training, learning paths, books, interactive tutorials, and more.

Start Free Trial

No credit card required