odbc_binmode

(PHP 4, PHP 5, PHP 7)

odbc_binmode — Handling of binary column data

Description

bool odbc_binmode ( resource $result_id , int $mode )

Enables handling of binary column data. ODBC SQL types affected are BINARY, VARBINARY, and LONGVARBINARY.

When binary SQL data is converted to character C data, each byte (8 bits) of source data is represented as two ASCII characters. These characters are the ASCII character representation of the number in its hexadecimal form. For example, a binary 00000001 is converted to "01" and a binary 11111111 is converted to "FF".

**LONGVARBINARY handling**
binmode	longreadlen	result
`ODBC_BINMODE_PASSTHRU`	0	passthru
`ODBC_BINMODE_RETURN`	0	passthru
`ODBC_BINMODE_CONVERT`	0	passthru
`ODBC_BINMODE_PASSTHRU`	0	passthru
`ODBC_BINMODE_PASSTHRU`	>0	passthru
`ODBC_BINMODE_RETURN`	>0	return as is
`ODBC_BINMODE_CONVERT`	>0	return as char

If odbc_fetch_into() is used, passthru means that an empty string is returned for these columns.

Parameters

result_id

The result identifier.

If result_id is 0, the settings apply as default for new results.

Note: Default for longreadlen is 4096 and mode defaults to ODBC_BINMODE_RETURN. Handling of binary long columns is also affected by odbc_longreadlen().

mode

Possible values for mode are:

ODBC_BINMODE_PASSTHRU: Passthru BINARY data
ODBC_BINMODE_RETURN: Return as is
ODBC_BINMODE_CONVERT: Convert to char and return

Return Values

Returns TRUE on success or FALSE on failure.

User Contributed Notes

yhalmoe at yahoo dot no

6 years ago


For Sybase users (this probably applies to MS-SQL Server as well) who are using ODBC:



I was using the same code as mizmerize, but I was getting truncated data back from the server (at the 32kb mark) when selecting data with the image datatype. My Sybase server has a @@textsize property of 2Gb, which should be plenty. But apparently, the php ODBC driver resets this to 32Kb when a connection is made, and then sets it back to 2Gb after. The solution is to do a query:



<?php odbc_exec($connH, "set textsize 131072"); ?>



immediately before your main query, in mizmerize's code. That should override the default setting.

mizmerize at yahoo dot com

10 years ago


I am currently using an SQL Server 2000 used as a datasource for ODBC access, Testing PHP scripts from an Apache 2 server running on Windows 2000.

I was trying to get an image from the database using ODBC but the output always flushes automatically while I was just getting the result using odbc_result() function.

With this code, the picture automatically prints to the browser as soon as I hit odbc_result() (probably a bug, but bug reports aren't that easy to do).

<?php
  $connH=odbc_pconnect("ImageDB","sa","",SQL_CUR_USE_IF_NEEDED) or die(odbc_errormsg());
    $result=odbc_exec($connH, "SELECT Emp_Image FROM tblEmployeePics WHERE Emp_Id=547");
    if ($result) {                            
        odbc_longreadlen($result, 131072);        
        odbc_binmode($result,ODBC_BINMODE_PASSTHRU);                            
//upon calling this, the output flushes out to the browser... made me scratch        
$m_FValue=odbc_result($result, 1);
}
?>

...after 48 hours of scratching I finally made a work around, but by using a function in the bin2hex() function documentation...

<?php
      function hex2bin($data){ 
       $len = strlen($data); 
       return pack("H" . $len, $data); 
    } 

    
    $connH=odbc_pconnect("ImageDB","sa","",SQL_CUR_USE_IF_NEEDED) or die(odbc_errormsg());
    $result=odbc_exec($connH, "SELECT Emp_Image FROM tblEmployeePics WHERE Emp_Id=547");
    if ($result) {                            
        odbc_longreadlen($result, 131072);        
        odbc_binmode($result,ODBC_BINMODE_CONVERT);                            
        $m_FValue=odbc_result($result, 1);
        $out=hex2bin($m_FValue);
    }
?>

The trick was to convert the output into hex by changing odbc_binmode to  ODBC_BINMODE_CONVERT and using a handy function to convert it back to binary in order to facilitate manipulation of its size, depth etc...

bortuzar

7 years ago


I set the odbc_longreadlen() at the beggining of my script so nText field types dont get truncated, like this:



<?php odbc_longreadlen (0, 1000000); ?>

andrea dot galli at acotel dot com

13 years ago


Example: retrieve image from database.

<?php

   $Link_ID = odbc_connect("DSN", "user", "pass"); 
   $Query_ID = odbc_exec($Link_ID, "SELECT picture FROM categories"); 

   // change to ODBC_BINMODE_CONVERT for comparison 

   odbc_binmode($Query_ID, ODBC_BINMODE_RETURN);

   $Images = odbc_result($Query_ID, 1);

   echo $Images;

?>