Using IBM DB2 with unixODBC
I have had a number of requests from people wanting to connect to IBM's DB2
from Linux via unixODBC. This short document details what I know about this at
the moment. If anyone can contribute more imformation then please contact me
at the address at the end of the document.
This document originally refered to the 6.1 version of DB2, since then I have
tried the 7.1 build and with a couple of changes, these are detailed at the
end of this document.
First, install the DB2 Client access package from IBM it will install the IBM
CLI driver, this works with unixODBC as a ODBC driver.
Using the install in the Client Access package, setup the client access to
give you a instance name (ie db2inst1), then setup your odbcinst.ini entry
Description = DB2 Driver
Driver = /usr/IBMdb2/V6.1/lib/libdb2.so
FileUsage = 1
DontDLClose = 1
The DontDLClose is required to avoid a problem in the driver when dynamically
loaded (I suspect its registering a exit function which isn't being called).
Then setup your odbc.ini like this.
Description = Test to DB2
Driver = DB2
(Driver 를 DB2를 넣으면 않되더라고요. 그래서 /usr/IBMdb2/V7.1/lib/libdb2.so 넣으면 되요)
Then when it comes to connecting, you MUST have the environment variable
DB2INSTANCE set to a vaild db2 instance, so for instance to connect with isql
isql -v sample db2inst1 ibmdb2
That should be all there is to it.
Since originally creating this document, IBM have released a new version of
DB2 7.1. I have tried the 7.1 build and with a couple of changes, the same
method seems to work fine. The only difference being the name of the package,
where the document used to refer to the DB2 Client access package, the CLI
driver is now to be found in the DB2 Personal Developer's Edition V7.1.
If using the 7.1 build the path to the library is now
Driver = /usr/IBMdb2/V7.1/lib/libdb2.so
I have also found that you need to add "/usr/IBMdb2/V7.1/lib" to /etc/ld.so.conf.
It has been reported that this installation doesn't work in some situations.
the attempt to open the driver fails, and cannot find a symbol sqltevents in
libdpdcf.a. I hav'nt had this problem, so I wonder if there is a difference
between platform, or builds of the DB2 instance. If anyone has any more info
on this let me know.
Another useful hint. Somewho has been using PHP+DB2 on AIX via unixODBC to a
BIG IBM server (4 processors, bags of core etc), and finding it was slow. It
turns out there is a bug in IBM's TCP/IP stack. after looking at this and
$ su - db2inst1
$ db2set DB2TCPCONNMGRS=1
To quote "... the difference was UNBELIEVABLE !!!". Thanks Eric.
If this is of any help to someone, good, any problems let me know.
출처 : http://www.unixodbc.org/doc/db2.html