8
OCCI Classes and Methods

This chapter describes the OCCI classes and methods for C++.

The topics discussed include:

Summary of OCCI Classes

Table 8-1 provides a brief description of all the OCCI classes. This section is followed by detailed descriptions of each class and its methods.

Table 8-1 OCCI Classes

Class	Description
Bfile Class	Provides access to a SQL BFILE value.
Blob Class	Provides access to a SQL BLOB value.
Bytes Class	Examines individual bytes of a sequence for comparing bytes, searching bytes, and extracting bytes.
Clob Class	Provides access to a SQL CLOB value.
Connection Class	Represents a connection with a specific database.
ConnectionPool Class	Represents a connection pool with a specific database.
Date Class	Specifies abstraction for SQL DATE data items. Also provides formatting and parsing operations to support the OCCI escape syntax for date values.
Environment Class	Provides an OCCI environment to manager memory and other resources of OCCI objects. An OCCI driver manager maps to an OCI environment handle.
IntervalDS Class	Represents a period of time in terms of days, hours, minutes, and seconds.
IntervalYM Class	Represents a period of time in terms of year and months.
Map Class	Used to store the mapping of the SQL structured type to C++ classes.
MetaData Class	Used to determine types and properties of columns in a `ResultSet`, that of existing schema objects in the database, or the database as a whole.
Number Class	Provides control over rounding behavior.
PObject Class	When defining types, enables specification of persistent or transient instances. Class instances derived from `PObject` can be either persistent or transient. If persistent, a class instance derived from `PObject` inherits from the `PObject` class; if transient, there is no inheritance.
Ref Class	The mapping in C++ for the SQL REF value, which is a reference to a SQL structured type value in the database.
RefAny Class	The mapping in C++ for the SQL REF value, which is a reference to a SQL structured type value in the database.
ResultSet Class	Provides access to a table of data generated by executing an OCCI `Statement`.
SQLException Class	Provides information on database access errors.
Statement Class	Used for executing SQL statements, including both query statements and insert / update / delete statements.
Stream Class	Used to provide streamed data (usually of the LONG datatype) to a prepared DML statement or stored procedure call.
Timestamp Class	Specifies abstraction for SQL TIMESTAMP data items. Also provides formatting and parsing operations to support the OCCI escape syntax for time stamp values.

OCCI Classes and Methods

OCCI classes are defined in the oracle::occi namespace. An OCCI class name within the oracle::occi namespace can be referred to in one of three ways:

Use the scope resolution operator (::) for each OCCI class name.
Use the using declaration for each OCCI class name.
Use the using directive for all OCCI class name.

Scope Resolution Operator

The scope resolution operator (::) is used to explicitly specify the oracle::occi namespace and the OCCI class name. To declare myConnection, a Connection object, using the scope resolution operator, you would use the following syntax:

oracle::occi::Connection myConnection;

using Declaration

The using declaration is used when the OCCI class name can be used in a compilation unit without conflict. To declare the OCCI class name in the oracle::occi namespace, you would use the following syntax:

using oracle::occi::Connection;

Connection now refers to oracle::occi::Connection, and myConnection can be declared as:

Connection myConnection;

using Directive

The using directive is used when all OCCI class names can be used in a compilation unit without conflict. To declare all OCCI class names in the oracle::occi namespace, you would use the following syntax:

using oracle::occi;

Then, just as with the using declaration, the following declaration would now refer to the OCCI class Connection:

Connection myConnection;

8 OCCI Classes and Methods