The Relational DAS provides two classes: the Relational DAS itself and
the subclass of Exception that can be thrown. The Relational DAS has
four publicly useful calls: the constructor,
the
createRootDataObject()
call to obtain the root object of an empty data graph,
the
executeQuery()
call to obtain a data graph containing data from a relational database,
and the
applyChanges()
call to write changes made to a data graph back to the relational
database.
SDO_DAS_Relational
The only object other than an SDO_DAS_Relational_Exception with which
the application is expected to interact.
Methods
__construct
- construct the Relational DAS with a model derived from the
passed metadata
createRootDataObject
- obtain an otherwise empty data graph containing just the special
root object
executeQuery
- execute an SQL query passed as a literal string and return
the results as a normalised data graph
executePreparedQuery
- execute an SQL query passed as a prepared statement, with a
list of values to substitute for placeholders, and return the
results as a normalised data graph
applyChanges
- examine the change summary in the data graph and apply those
changes back to the database, subject to an assumption
of optimistic concurrency
SDO_DAS_Relational_Exception
Is a subclass of PHP's
Exception.
It adds no behaviour to
Exception.
Thrown, with useful descriptive text, to signal errors in the
metadata or unexpected failures to perform SQL operations.
SDO_DAS_Relational::executePreparedQuery — Executes an SQL query passed as a prepared statement, with a
list of values to substitute for placeholders, and return the
results as a normalised data graph.
SDO_DAS_Relational::executeQuery — Executes a given SQL query against a relational database
and returns the results as a normalised data graph.
Load balance : Server 04
