SDO-DAS-Relational 函数

预定义类

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.

方法

• __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.

Table of Contents

• SDO_DAS_Relational::applyChanges — Applies the changes made to a data graph back to the database
• SDO_DAS_Relational::__construct — Creates an instance of a Relational Data Access Service
• SDO_DAS_Relational::createRootDataObject — Returns the special root object in an otherwise empty data graph. Used when creating a data graph from scratch
• 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