Oratcl is a dynamic extension of the Tcl language that integrates Oracle OCI calls into a set of Tcl commands that allow Oracle access via Tcl.


Sourceforge project page
Todd M. Helfter
Tom Poindexter


current version




User's Guide and Reference
man page
OraTcl Description ,Oracle Intelligent Agent User's Guide, release
OraTclkkOracle Intelligent Agent User's Guide, release
Introduction to OraTcl ,Tom Poindexter
Tom Poindexter's Oratcl page
last updated in 1999


Cinderella Languages Cameron Laird Kathryn Soraiz 1999

See Also

uses OraTcl
uses OraTcl internally
Programming Oracle stored-procedure cursors
oratcl examples
Oratcl Logon Dialog
Plotting data
Oracle Programming with Tcl & Oratcl ,Jeff Hunter


OraTcl 3 and up supports Tcl 8 (tclX recommended), and supports Tcl 8.x, includes Windows NT DLLs, cursor variables from PL/SQL, can bind Tcl variables to orafetch results, can bind Tcl variables to Oracle :bind variables, supports asynchronous SQL execution. It supports Tcl/Tk 8.x, Oracle 7/8/8i/9i/10g/11g, i18n data, and TEA/Stubs as well as Solaris and Windows NT. Oracle has released a version of its 8.0.5 database product for Linux at the oracle web site.

Oratcl was one of the first, and remains one of the most widely-used, examples of a third-party language interacting with databases. Oracle has only acknowledged Oratcl's existence though ([L1 ]), always documenting use of its core RDBMS product in terms of C, its proprietary PL/SQL, and, in recent years, Java.


OraTcl 2.5 was the last version to support Tcl 7.6.

Oratcl Tips

Insert your favorite Oratcl tips, tricks, and hints, etc. here. Also, point to various useful reading, such as BOOK Tcl/Tk Tools, or BOOK Oracle and Open Source.

Oratcl binary data tips

Also add here information about tips for managing Unicode, images, etc. from within Oracle tables.

One thing that was discovered is that one needs to set something called the NLS before starting oracle and attempting to deal with UTF-8 data. This can be done using the NLS_LANG environment variable, or using something like SQLPLUS's alter session set nls_territory and alter session set nls_language to appropriate values.

Apparently, as long as NLS_LANG is set to some valid language, oracle then handles a localization sweep over the data properly before handing the data back to the requestor. Then, you do a call to

encoding convertfrom utf-8 $string

and off you go.

Oratcl dependance on Oracle

Todd points out that, "OraTcl relies on the Oracle install. This means different things on different platforms.

On Unix, the ORACLE_HOME environment variable must point to a valid Oracle install.

On windows, the ociw32.lib file must be found in the WINDOWS search path. In the past, I have had to place the oracle directory in the windows PATH variable in autoexec.bat. In later releases, the registry information was sufficient to find the file."

Installing Oratcl on Windows

Laurent Riesterer 2005-09-23: The easiest way to install the required library (tested on Windows) is to use the "Oracle Instant Client" setup. You just need to unzip the content of one file in a folder (about 80 MB), add this folder to you path and then you can start to use Oratcl. You don't need any configuration file, just use a fully qualified name in your connection string:


Oratcl programming style question

LV: For which version of Oratcl is this template - I seem to recall that at version changes, the paradigm used by oratcl programs had to change...

A recent article on comp.lang.tcl by Kevin Rodgers asked for comments about this sample boilerplate:

# For error reporting:
set program [file tail $argv0]

# Package interface:
package require Oratcl

# Connect to the $env(TWO_TASK) database as USER with PASSWORD:
if [catch {oralogon "USER/PASSWORD"} ora_logon] {
   puts stderr "$program: $ora_logon"
   exit 1
if [catch {oraopen $ora_logon} ora_statement] {
   oralogoff $ora_logon
   puts stderr "$program: $ora_statement"
   exit 1
#if [catch {oraconfig $ora_statement fetchrows 1024} ora_error] {
#    puts stderr "$program: $ora_error"

# Execute SQL statement:
set sql "SELECT column_1, ... column_N FROM ... WHERE ..."
# Note that for Oratcl 4.x, the $oramsg references have to change to
# [oramsg $ora_statement rc]
if [catch {orasql $ora_statement $sql} ora_error] {
   puts stderr "$program: $ora_error"
} elseif {$oramsg(rc) != 0} {
   puts stderr "$program: $oramsg(errortxt)"
} else {
   # Process each row with column_I bound to var_I:
   while {$oramsg(rc) == 0} {
       if [catch {orafetch $ora_statement \
                           {... $var_1 ... $var_N ...} \
                           '@' var_1 1 ... var_N N} \
                 ora_error] {
           puts stderr "$program: $ora_error"
       } elseif {$oramsg(rc) == 1403} {
       } elseif {$oramsg(rc) != 0} {
           puts stderr "$program: $oramsg(errortxt)"

# Disconnect from the $env(TWO_TASK) database:
if [catch {oraclose $ora_statement ora_error] {
   puts stderr "$program: $ora_error"
if [catch {oralogoff $ora_logon ora_error] {
   puts stderr "$program: $ora_error"

Intro to Oratcl reference

See also http://www.dbcorp.com/downloads/ORATCL.ppt for an intro to Oratcl (and Oracle's OEM) from 2000.

Addition of pointers to other Oratcl tutorials - particular current ones - would be greatly appreciated.

RLH: I would like to second the request for tutorials and example pointers. I am new to Tcl and while I can use Perl/DBI to do what I want, I would rather use Tcl. :-)

Installing Oratcl on MacOS X

Kroc 2006-10-18:

OraTcl relies on the Oracle install but that's not so easy to install Oracle client on Mac OS X. Here are the steps I followed to get something that works:

1) Download Oracle client 8.1.7:

The file to get is Oracle 8i v8.1.7.1 OCI / Mac OS X from this page: http://www.oracle.com/technology/software/tech/java/sqlj_jdbc/htdocs/macsoft.html (you must register to get it but it's free).

Uncompress MacOSX_8171.cpio and you'll get 3 files: MacOSX_8.1.7.1_OCI_Demo.zip, Oracle_8.1.7.1_Client.zip et Release_Notes.zip.

2) Client installation:

Uncompress Oracle_8.1.7.1_Client.zip then move Oracle_8.1.7.1_Client directory in your home.

Then you must edit ~/Oracle_8.1.7.1_Client/network/admin/tnsnames.ora to fit your server parameters. At the end, it should be something like this:

         (ADDRESS_LIST =
             (ADDRESS = (PROTOCOL = TCP)(HOST = = 1521))
         (SID = MYBASE)

3) Environment variable:

At least one environment variable, ORACLE_HOME, must be set before loading OraTcl:

 set ::env(ORACLE_HOME) [file normalize ~/Oracle_8.1.7.1_Client]

Tested on Mac OS X 10.4.8 with OraTcl 4.4

Oracle 10 and OraTcl

Note that Oracle 10 brings, at least on some platforms, another wrinkle. For me, on a SPARC Solaris 9 system, Oracle 10 defaults to 64 bit libraries. If you are using ActiveTcl or something similar, you will find that oratcl was compiled as a 32 bit interface. This means that you need to use the environment varirable:

# For 32 bit tcl on 64 bit solaris with 64 bit oracle.
export ORACLE_LIBRARY=$ORACLE_HOME/lib32/libclntsh.so

so that oratcl can be loaded. This is not a bug in oratcl. It is the mechanism that Oracle provides for someone to use the 32 bit libraries. You just need to know whether you are using a 32 bit or a 64 bit tcl so that you get the correct shared libraries.


older versions of OraTcl included wosql, but it didn't work with newer versions, so was removed from the distribution. Susan Emma announced that she had modified wosql to work with OraTcl 4, but that code is currently lost.

Note about orafetch

LV 2008-1117:

In moving from oratcl 4.2 to 4.4, I noticed a difference in behavior in one of my programs. Turns out that in my program I used:

orafetch ... -command { name }

In my program, the name proc returned without specifying an argument. In oratcl 4.2, the program worked fine. In oratcl 4.4, the return code from orafetch appears to have become the return value from name. I changed name to return 0 instead of nothing, and my program worked again.

In my case, this was a better coding style anyways, so it worked out well. Just wanted to be certain that anyone else encountering peculiar behavior thinks of this.

LV 2009-01-21:

I have a situation for which I'm looking for a solution.

I have two data sources - one, a flat text file, containing deliminated fields of information. The first field is an item identifier.

The second data source is an oracle table, where each column corresponds to the fields from the flat file and the rows should correspond to each line.

What I am wanting to end up with is a program that reports items from the flat file that are not found in the table, and items in the table which are not found in the flat file.

I supposed I could dynamically generate a select statement with a where col_name not in (val1, val2, ...., val2000) type statement, but I was wondering if anyone had other ideas of ways to approach the situation.

Harm Olthof 2009-01-22:

There are quite a few solutions from the Oracle side.

(1) you can import the flat file into your database, using sqlloader;

(2) From Oracle version 9.x and higher you can also link it, using the concept of "External Tables";

(3) Oracle also has a [webdav] solution, but this not generally made available by the dba-er. I think [ftp] is also possible;

(4) You could convert your flat file to xml and then there are more sophisticated possibilities; All of these possibilities expose the flat file as a table and then you can do a "..where not exists.." query. Oracle has a kind of combination of our wiki and a newsgroup, run by Tom Kyte on: [L2 ]. If you go there and search for things like sqlloader, external tables, csv, flat file etc. you'll find a lot of explanations and examples. No [Tcl] solution. It would be great if someone wrote a tcl Oracle Cartridge so we could use tcl instead of pl/sql.

thelfter - 2017-09-22 17:01:24

I am adding new features to Oratcl. If you have any feature requests -- please pass them along.

MHo 2022-04-13: It´s not so easy to connect to a pluggable Database (PDB) as sysdba. One can set ORACLE_SID beforehand, or the standard system settings are used, but then you get logged in to the Container Databae (CDB). And there you have to execute the command alter session set container=PDBNAME if you want to operate against the PDB. Setting ORACLE_PDB_SID beforehand does not work (saw it somewhere), not in conjunction with oratcl i think).