The Oracle Call Interface (OCI) is an application programming interface (API) that allows applications written in C or C++ to interact with one or more Oracle database servers. OCI gives your programs the capability to perform the full range of database operations that are possible with an Oracle database server, including SQL statement processing and object manipulation.


This guide is intended for programmers developing new applications or converting existing applications to run in the Oracle environment. This comprehensive treatment of OCI will also be valuable to systems analysts, project managers, and others interested in the development of database applications.

This guide assumes that you have a working knowledge of application programming using C. Readers should also be familiar with the use of Structured Query Language (SQL) to access information in relational database systems. In addition, some sections of this guide also assume a knowledge of the basic concepts of object-oriented programming.

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Related Documents

Many of the examples in this book use the sample schemas, which are installed by default when you select the Basic Installation option with an Oracle Database installation. Refer to Oracle Database Sample Schemas for information on how these schemas were created and how you can use them yourself.

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The Oracle Call Interface Programmer's Guide does not contain all information that describes the features and functionality of OCI in the Standard Edition and the Enterprise Edition products.

Oracle C++ Call Interface

For C++ programmers, the Oracle C++ Call Interface provides OCI functionality for C++ programs and lets you manipulate database objects (of user-defined types) as C++ objects.

Other Sources of Information about OCI

For other sources of information about OCI:

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Further Sources of Information About Oracle Database


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