# ODBC initialization issues

**URL:** <https://discourse.julialang.org/t/odbc-initialization-issues/3241>\
**Category:** Data\
**Created:** [April 16, 2017, 7:25pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241 "2017-04-16T19:25:34Z")\
**Posts on this page:** 8\
**Page:** 1

<div class="post-metadata">

**Author:** ![jkbest2](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jkbest2/32/7350_2.png) [@jkbest2](https://discourse.julialang.org/u/jkbest2)\
**Post date:** [April 16, 2017, 7:25pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/1 "2017-04-16T19:25:34Z")

</div>

I have successfully used `ODBC.jl` to retrieve data from a PostgreSQL server in the past (on Ubuntu). I’m trying to recreate my setup on Arch Linux, and running into problems when I load the `ODBC` package. I am using the same `odbcinst.ini` and `odbc.ini` files (in `/etc`), and I have the `psqlodbc` v9.03.0400-2 and `unixodbc` v2.3.4-2 Arch packages installed.

```julia
julia> using ODBC
ERROR: InitError: ccall: could not find function SQLAllocHandle in library 
 in SQLAllocHandle(::Int16, ::Ptr{Void}, ::Base.RefValue{Ptr{Void}}) at ~/.julia/v0.5/ODBC/src/API.jl:63
during initialization of module ODBC

```

This is on Julia v0.5.1 and ODBC.jl v0.5.2.

Outside of Julia, I am able to connect to the database and retrieve queries using `isql`, and my installed drivers show up when I using `odbcinst -q -d`:

```julia
> odbcinst -q -d
[PostgreSQL ANSI]
[PostgreSQL Unicode]

```

I expect this is a setup error on my end, but I’m not quite sure how to go about fixing it. I’d appreciate any suggestions.

Thanks in advance!

---

<div class="post-metadata">

**Author:** ![quinnj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/quinnj/32/11_2.png) [@quinnj](https://discourse.julialang.org/u/quinnj)\
**Post date:** [April 17, 2017, 2:25pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/2 "2017-04-17T14:25:40Z")

</div>

Most likely there’s some problem detecting the correct ODBC shared library. For linux, the library names that are tried are

```julia
lib_choices = ["libodbc", "libodbc.so", "libodbc.so.1", "libodbc.so.2", "libodbc.so.3"]

```

You can check which one is selected by doing

```julia
using ODBC
ODBC.API.odbc_dm

```

If you can tell which library _should_ be getting set (maybe by looking in `/usr/lib/`), then you can do

```julia
ODBC.API.setODBC(libname)

```

to actually set the library.

---

<div class="post-metadata">

**Author:** ![jkbest2](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jkbest2/32/7350_2.png) [@jkbest2](https://discourse.julialang.org/u/jkbest2)\
**Post date:** [April 17, 2017, 6:57pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/3 "2017-04-17T18:57:49Z")

</div>

When I check `ODBC.API.odbc_dm`, I get

```julia
julia> using ODBC
julia> ODBC.API.odbc_dm
""

```

So it doesn’t seem to be finding anything. When I look in `/usr/lib`, I get

```julia
> cd /usr/lib
> ls *odbc*
libodbccr.so libodbcinst.so libodbc.so psqlodbcw.so
libodbccr.so.2 libodbcinst.so.2 libodbc.so.2
libodbccr.so.2.0.0 libodbcinst.so.2.0.0 libodbc.so.2.0.0

tdbcodbc1.0.4:
libtdbcodbc1.0.4.so pkgIndex.tcl tdbcodbc.tcl

```

So the library is present. After `using ODBC`, I tried to set the library manually, using `libodbc`, `libodbc.so` and `/usr/lib/libodbc.so`. I get a warning about `redefining constant odbc_dm` that I’m not worried about, but if I try `ODBC.listdrivers()` or `ODBC.listdsns()`, I get

```julia
ERROR: UndefVarError: ENV not defined
 in listdrivers() at ~/.julia/v0.5/ODBC/src/ODBC.jl:72
 in eval_user_input(::Any, ::Base.REPL.REPLBackend) at ./REPL.jl:64
 in macro expansion at ./REPL.jl:95 [inlined]
 in (::Base.REPL.##3#4{Base.REPL.REPLBackend})() at ./event.jl:68

```

Do you have any other suggestions? Thanks again.

---

<div class="post-metadata">

**Author:** ![nalimilan](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nalimilan/32/147_2.png) [@nalimilan](https://discourse.julialang.org/u/nalimilan)\
**Post date:** [April 17, 2017, 8:14pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/4 "2017-04-17T20:14:48Z")

</div>

Maybe the library wasn’t present when you first installed the package? Call `Pkg.build("ODBC")` to run the detection script again.

---

<div class="post-metadata">

**Author:** ![jkbest2](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jkbest2/32/7350_2.png) [@jkbest2](https://discourse.julialang.org/u/jkbest2)\
**Post date:** [April 17, 2017, 9:09pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/5 "2017-04-17T21:09:12Z")

</div>

The library was not present when I installed the package (oops). But rebuilding `ODBC` doesn’t seem to run the detection script:

```julia
julia> Pkg.build("ODBC")
INFO: Building DecFP

```

Then `using ODBC` gives me the same errors as above, and `ODBC.API.odbc_dm` is an empty string.

---

<div class="post-metadata">

**Author:** ![rdeits](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/rdeits/32/286_2.png) [@rdeits](https://discourse.julialang.org/u/rdeits)\
**Post date:** [April 17, 2017, 9:36pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/6 "2017-04-17T21:36:41Z")

</div>

Some build results will be cached in, for example, the `deps/deps.jl` file. One easy way to delete those is:

```julia
cd ~/.julia/v0.5/ODBC
git clean -f -x

```

Warning: this will delete any files inside the ODBC package directory which are not committed in git. If you have any new files or local modifications to that package, don’t do this.

After running `git clean`, you should be able to run `Pkg.build("ODBC")` in julia and get a clean re-build.

---

<div class="post-metadata">

**Author:** ![jkbest2](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/jkbest2/32/7350_2.png) [@jkbest2](https://discourse.julialang.org/u/jkbest2)\
**Post date:** [April 17, 2017, 9:55pm UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/7 "2017-04-17T21:55:05Z")

</div>

Unfortunately that didn’t work. But for some reason deleting the directory and running `Pkg.update()` to reinstall it did work. It now detects my drivers and DSNs correctly.

Thanks for the help everyone!

---

<div class="post-metadata">

**Author:** ![quinnj](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/quinnj/32/11_2.png) [@quinnj](https://discourse.julialang.org/u/quinnj)\
**Post date:** [April 18, 2017, 6:10am UTC](https://discourse.julialang.org/t/odbc-initialization-issues/3241/8 "2017-04-18T06:10:38Z")

</div>

Ah yes, I guess the current form of `setODBC` isn’t quite enough if you’re actually going to redefine the library, it needs to, rather, be something like

```julia
function setODBC(x)
    eval(ODBC.API, :(odbc_dm = $x))
    eval(ODBC, :(ENV = ODBC.ODBCAllocHandle(ODBC.API.SQL_HANDLE_ENV, ODBC.API.SQL_NULL_HANDLE))
end

```