Oracle Call Interface (OCI) is an application programming interface (API) that lets applications written in C or C++ interact with Oracle Database. OCI gives your programs the capability to perform the full range of database operations that are possible with Oracle Database, 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 Database environment. This comprehensive treatment of OCI is also 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 assume 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. See Oracle Database Sample Schemas for information about how these schemas were created and how you can use them.

To download free release notes, installation documentation, white papers, or other collateral, visit the Oracle Technology Network (OTN). You must register online before using OTN; registration is free and can be done at

If you have a user name and password for OTN, then you can go directly to the documentation section of the OTN Web site at

Oracle Call Interface Programmer's Guide does not contain all information that describes the features and functionality of OCI in the Oracle Database Standard Edition and Enterprise Edition products. Explore the following documents for additional information about OCI.

For additional information about Oracle Database, consult the following documents:


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