| org.apache.derby.vti |
|
| Java Source File Name | Type | Comment |
| DeferModification.java | Interface | This interface is implemented by a read/write VTI class that wants to control when
modifications to the VTI are deferred, or to be notified that a it is to be modified.
Consider the following statement:
UPDATE NEW myVTI(...)
SET cost = cost + 10
WHERE cost < 15
Updating a column that is used in the WHERE clause might or might not give the VTI implementation trouble;
the update might cause the same row to be selected more than once. |
| IFastPath.java | Interface | An internal api for VTIs to allow VTI's written
in terms of the datatype system, e.g. |
| IQualifyable.java | Interface | |
| Pushable.java | Interface | Support for pushing SQL statement information
down into a virtual table. |
| UpdatableVTITemplate.java | Class | An abstract implementation of PreparedStatement (JDK1.1/JDBC 1.2) that is useful
when writing a read-write (updatable) virtual table interface (VTI).
This class implements
the methods of the JDBC1.2 version of PreparedStatement plus the
JDBC2.0 getMetaData() method, each one throwing a SQLException
with the name of the method. |
| VTICosting.java | Interface | VTICosting is the interface that the query optimizer uses
to cost VTIs.
The methods on the interface provide the optimizer
with the following information:
- the estimated number of rows returned by the VTI in a single instantiation.
- the estimated cost to instantiate and iterate through the VTI.
- whether or not the VTI can be instantiated multiple times within a single query execution
This class can only be used within an SQL-J statement. |
| VTIEnvironment.java | Interface | VTIEnvironment is an interface used in costing VTIs. |
| VTIMetaDataTemplate.java | Class | An abstract implementation of ResultSetMetaData (JDBC 1.2) that is useful
when writing a VTI (virtual table interface).
This class implements
most of the methods of ResultSetMetaData, each one throwing a SQLException
with the name of the method. |
| VTITemplate.java | Class | An abstract implementation of ResultSet (JDK1.1/JDBC 1.2) that is useful
when writing a read-only VTI (virtual table interface) or for
the ResultSet returned by executeQuery in read-write VTI classes.
This class implements most of the methods of the JDBC 1.2 interface java.sql.ResultSet,
each one throwing a SQLException with the name of the method. |