Indexes for AR System tables
The main data table has an index supported by AR System defined for the C1 column. This column corresponds to the Request ID field of the form. The index is a unique index and is used extensively as the main index of the table. In Microsoft SQL Server databases, the table is created by using a primary key, which enables database replication.
For the main data table, the administrator can create additional indexes for the form. The indexes are unique only if defined as such. These additional indexes are not clustered because there can be only one clustered index, and it is reserved for the main index supported by AR System.
The status history table has an index supported by AR System defined on the entryId column. This column also corresponds to the Request ID field of the form. The index is a unique clustered index and is the main index of the table. AR System does not create additional indexes for the status history table.
The Attachment Data and the Attachment Details tables each have unique indexes supported by AR System. For the Attachment Data table, the index is defined on the entryId column, and for the Attachment Details table, the index is defined on the C1 column. These columns correspond to the Request ID field of the form. The administrator cannot create additional indexes.
Indexing a currency field requires special considerations. Because a currency field is represented by multiple columns in the main data table, multiple columns are indexed. Standard queries against a currency field could potentially use any of several different columns, depending on the currency type specified.
To provide comprehensive coverage, indexing a currency field requires an index for the value column, the type column, and for each functional currency column. This can produce significant overhead for the main data table. Therefore, consider indexing a currency field carefully before doing so.
Indexes cannot be created for join forms. The form definition is just a view and the database does not support indexes for views. Indexes defined for the underlying tables are available and are used when performing operations against the join form. For view forms, you must create indexes within the database. The AR System cannot create indexes on the view of the external database's table. For vendor forms, the administrator who implemented the ARDBC data source must define and document a mechanism to establish indexes on the underlying data. For more information about ARDBC, see the Developing an API application.