| Server IP : 103.119.228.120 / Your IP : 3.15.228.32 Web Server : Apache System : Linux v8.techscape8.com 3.10.0-1160.119.1.el7.tuxcare.els2.x86_64 #1 SMP Mon Jul 15 12:09:18 UTC 2024 x86_64 User : nobody ( 99) PHP Version : 5.6.40 Disable Function : shell_exec,symlink,system,exec,proc_get_status,proc_nice,proc_terminate,define_syslog_variables,syslog,openlog,closelog,escapeshellcmd,passthru,ocinum cols,ini_alter,leak,listen,chgrp,apache_note,apache_setenv,debugger_on,debugger_off,ftp_exec,dl,dll,myshellexec,proc_open,socket_bind,proc_close,escapeshellarg,parse_ini_filepopen,fpassthru,exec,passthru,escapeshellarg,escapeshellcmd,proc_close,proc_open,ini_alter,popen,show_source,proc_nice,proc_terminate,proc_get_status,proc_close,pfsockopen,leak,apache_child_terminate,posix_kill,posix_mkfifo,posix_setpgid,posix_setsid,posix_setuid,dl,symlink,shell_exec,system,dl,passthru,escapeshellarg,escapeshellcmd,myshellexec,c99_buff_prepare,c99_sess_put,fpassthru,getdisfunc,fx29exec,fx29exec2,is_windows,disp_freespace,fx29sh_getupdate,fx29_buff_prepare,fx29_sess_put,fx29shexit,fx29fsearch,fx29ftpbrutecheck,fx29sh_tools,fx29sh_about,milw0rm,imagez,sh_name,myshellexec,checkproxyhost,dosyayicek,c99_buff_prepare,c99_sess_put,c99getsource,c99sh_getupdate,c99fsearch,c99shexit,view_perms,posix_getpwuid,posix_getgrgid,posix_kill,parse_perms,parsesort,view_perms_color,set_encoder_input,ls_setcheckboxall,ls_reverse_all,rsg_read,rsg_glob,selfURL,dispsecinfo,unix2DosTime,addFile,system,get_users,view_size,DirFiles,DirFilesWide,DirPrintHTMLHeaders,GetFilesTotal,GetTitles,GetTimeTotal,GetMatchesCount,GetFileMatchesCount,GetResultFiles,fs_copy_dir,fs_copy_obj,fs_move_dir,fs_move_obj,fs_rmdir,SearchText,getmicrotime MySQL : ON | cURL : ON | WGET : ON | Perl : ON | Python : ON | Sudo : ON | Pkexec : ON Directory : /usr/share/doc/unixODBC-2.3.1/doc/ProgrammerManual/Tutorial/ |
Upload File : |
<HTML>
<HEAD>
<META HTTP-EQUIV="Content-Type" content="text/html; charset=iso-8859-1">
<TITLE>Connecting </TITLE>
<LINK REL="StyleSheet" Href="odbc.css">
</HEAD>
<BODY bgcolor="white">
<table width="90%" cols="3" border="0">
<TR>
<TD colspan="3" class="big">Connecting to a Datasource</TD>
</TR>
<TR>
<TD colspan="3"><P>First thing you will need is a variable of type <CODE>SQLHENV</CODE>. This is
a handle (pointer) to an internal ODBC structure which holds all informationen about the
ODBC environment. Without a handle of that kind you won't be able do to very much.
To get this handle you call <CODE><A HREF="gloss.html#alloc">SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &V_OD_Env)</A></CODE>.
<CODE>V_OD_Erg</CODE> is a variable of type <CODE>SQLHENV</CODE> which holds the allocated environment handle.</P>
<P>
If you have allocated the handle you need to define which version of ODBC to use. Therefore
you should call <CODE><A HREF="gloss.html#envattr">SQLSetEnvAttr(V_OD_Env, SQL_ATTR_ODBC_VERSION, (void*)SQL_OV_ODBC3, 0)</A></CODE>.
The constant <CODE>SQL_ATTR_ODBC_VERSION</CODE> defines that the needed version of ODBC will be defined
and <CODE>SQL_OV_ODBC3</CODE> says that the program will need ODBC 3.0.
</P>
<P>Next thing to do is to create a handle for the database connection which is of the type <CODE>SQLHDBC</CODE>. Once again you call
<CODE>SQLAllocHandle</CODE> this time with <CODE>SQL_HANDLE_DBC</CODE> and the variable to the environment returned by the first call to
<CODE>SQLAllocHandle</CODE>.
</P><P>
Then you may choose to modify the connection attributes, mainly the timeout for any given
action on the connection. You do this by calling <CODE><A HREF="gloss.html#conattr">SQLSetConnectAttr</A></CODE>
with the connection handle, attribute and value pointer and the string length (if available).</P>
<P>
Finally we are able to connect to the database via <CODE><A href="gloss.html#conn">SQLConnect</A></CODE>, which needs the name of the data source,
the username and password as parameters. For each parameter you need to specify how long the string is or just gib <COde>SQL_NTS</CODE> which
says that it is a string which length has to be determined by <CODE>SQLConnect</CODE>
</P>
That's it, we are connected to the database. Please note, that all functions mentioned on this page return either <CODE>SQL_SUCCESS</CODE>, <CODE>SQL_SUCCESS_WITH_INFO</CODE>
if all went smoothly or <CODE>SQL_ERROR</CODE> or <CODE>SQL_INVALID_HANDLE</CODE> in case of an error. We will have a look on how to get diagnostic messages a little later.
<P>
So let's have a look at the code:
</TD>
</TR>
</TABLE>
<TABLE>
<TR>
<TD>
<PRE><CODE class="list">
<A NAME="list"></A>
/* odbc.c
testing unixODBC
*/
#include <stdlib.h>
#include <stdio.h>
#include <odbc/sql.h>
#include <odbc/sqlext.h>
#include <odbc/sqltypes.h>
SQLHENV V_OD_Env; <FONT COLOR="green">// Handle ODBC environment</FONT>
long V_OD_erg; <FONT COLOR="green">// result of functions</FONT>
SQLHDBC V_OD_hdbc; <FONT COLOR="green">// Handle connection</FONT>
char V_OD_stat[10]; <FONT COLOR="green">// Status SQL</FONT>
SQLINTEGER V_OD_err,V_OD_rowanz,V_OD_id;
SQLSMALLINT V_OD_mlen;
char V_OD_msg[200],V_OD_buffer[200];
int main(int argc,char *argv[])
{
<FONT COLOR="green">// 1. allocate Environment handle and register version </FONT>
V_OD_erg=SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&V_OD_Env);
if ((V_OD_erg != SQL_SUCCESS) && (V_OD_erg != SQL_SUCCESS_WITH_INFO))
{
printf("Error AllocHandle\n");
exit(0);
}
V_OD_erg=SQLSetEnvAttr(V_OD_Env, SQL_ATTR_ODBC_VERSION,
(void*)SQL_OV_ODBC3, 0);
if ((V_OD_erg != SQL_SUCCESS) && (V_OD_erg != SQL_SUCCESS_WITH_INFO))
{
printf("Error SetEnv\n");
SQLFreeHandle(SQL_HANDLE_ENV, V_OD_Env);
exit(0);
}
<FONT COLOR="green">// 2. allocate connection handle, set timeout</FONT>
V_OD_erg = SQLAllocHandle(SQL_HANDLE_DBC, V_OD_Env, &V_OD_hdbc);
if ((V_OD_erg != SQL_SUCCESS) && (V_OD_erg != SQL_SUCCESS_WITH_INFO))
{
printf("Error AllocHDB %d\n",V_OD_erg);
SQLFreeHandle(SQL_HANDLE_ENV, V_OD_Env);
exit(0);
}
SQLSetConnectAttr(V_OD_hdbc, SQL_LOGIN_TIMEOUT, (SQLPOINTER *)5, 0);
<FONT COLOR="green">// 3. Connect to the datasource "web" </FONT>
V_OD_erg = SQLConnect(V_OD_hdbc, (SQLCHAR*) "web", SQL_NTS,
(SQLCHAR*) "christa", SQL_NTS,
(SQLCHAR*) "", SQL_NTS);
if ((V_OD_erg != SQL_SUCCESS) && (V_OD_erg != SQL_SUCCESS_WITH_INFO))
{
printf("Error SQLConnect %d\n",V_OD_erg);
SQLGetDiagRec(SQL_HANDLE_DBC, V_OD_hdbc,1,
V_OD_stat, &V_OD_err,V_OD_msg,100,&V_OD_mlen);
printf("%s (%d)\n",V_OD_msg,V_OD_err);
SQLFreeHandle(SQL_HANDLE_ENV, V_OD_Env);
exit(0);
}
printf("Connected !\n");
<FONT COLOR="green">/* continued on next page */</FONT>
</CODE>
</PRE>
</TD>
</TR>
</TABLE>
</BODY>
</HTML>