Restrictions in IMA Use
Following is a summary of current restrictions within IMA:
• Support for data types is limited in table registrations.
– Only INTEGER, VARCHAR, and CHAR data types can be specified as data types in the REGISTER TABLE statement.
– All columns must be NOT NULL NOT DEFAULT.
• The IMA supports full SQL but with the following restrictions:
– There is no locking or lock ownership of IMA underlying objects.
– There are no transactions for updates for IMA objects.
– Updates take immediate action and cannot be rolled back.
– All reads are “dirty.” This means that querying the same object may return different values because the data underlying the record could have changed.
– Rule triggering is unreliable. Rules are not triggered when the value of an object changes in a way unknown through SQL. This occurs to IMA related data as the installation operates. Thus, while updates that are performed through SQL can trigger rules, rule integrity cannot be guaranteed for IMA data.
• The group of defined objects supplied with the IMADB database is subject to change in subsequent releases.
• A cluster installation is visible to IMA as the installations on each node within a domain.