<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <HTML ><HEAD ><TITLE >Connection error numbers and messages</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK REL="HOME" TITLE="Database Independent Abstraction Layer for C" HREF="index.html"><LINK REL="UP" TITLE="Error Handling" HREF="errorhandling.html"><LINK REL="PREVIOUS" TITLE="Error Handling" HREF="errorhandling.html"><LINK REL="NEXT" TITLE="Error numbers" HREF="errornumbers.html"></HEAD ><BODY CLASS="SECT1" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >Database Independent Abstraction Layer for C: libdbi Programmer's Guide</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="errorhandling.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" >Chapter 4. Error Handling</TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="errornumbers.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="SECT1" ><H1 CLASS="SECT1" ><A NAME="CONNERRORS" >4.1. Connection error numbers and messages</A ></H1 ><P >If your application has successfully opened a connection to a database, all operations on this connection may cause errors. There are two classes of errors:</P ><P ></P ><DIV CLASS="VARIABLELIST" ><DL ><DT >Client library errors</DT ><DD ><P >libdbi retrieves and stores the error codes of the database engine client library if it provides error codes in a suitable format. If the client library does not support error numbers as positive integers, the value DBI_ERROR_CLIENT indicates an error status instead. In addition a string may be provided which describes or further elaborates the error status. The possible values of error number and error message depend on the database engine used for the connection.</P ></DD ><DT >libdbi errors</DT ><DD ><P >A number of errors may occur within the libdbi framework or within a database driver, e.g. if your program queries nonexistent columns or attempts to read past the last row of a result set. The possible error numbers and error messages are predefined by libdbi.</P ></DD ></DL ></DIV ><P >Use the function <A HREF="reference-conn.html#DBI-CONN-ERROR" >dbi_conn_error</A > to access the error number and error message of the most recent connection operation.</P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="errorhandling.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="errornumbers.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >Error Handling</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="errorhandling.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >Error numbers</TD ></TR ></TABLE ></DIV ></BODY ></HTML >