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Overview | Environments | Databases | Tables | Indexes | Queries | Updates | Stored Procedures | Example
The Omnidex SQL Engine will optimize queries to take advantage of the Omnidex indexes. Many queries can be completed entirely within the Omnidex indexes. This is especially true for queries that request counts or aggregations from one or more tables. Even queries that return columns of data can be completed using the Omnidex indexes, as long as all of the data resides in an index.
Other queries will require access to the underlying Oracle data. The Omnidex SQL Engine will determine how to combine the results from the Omnidex indexes with the data from the Oracle database. Usually, this means that Omnidex provides Oracle rowids or primary keys and requests rows from the Oracle tables based on those values. Other times, Omnidex may issue a more complex statement to Oracle, asking it to perform a larger role in processing the query.
In all cases, Omnidex will access the data in the Oracle database using standard Oracle SQL statements issued using the Oracle Call Interface (OCI).
Omnidex requires that all statements use Omnidex SQL syntax. Omnidex SQL uses ANSI SQL as a base, but also allows extensions from various database, as well as Omnidex-specific extensions. Omnidex SQL does support some Oracle-specific functions, including:
Other Oracle-specific syntax will cause errors when submitted to Omnidex. In these situations, the statements must be converted to Omnidex SQL.
See also: