Accessing SQL Server Data

from Oracle on Linux

for FREE!

COUG15-NOV-2012

Wayne Linton

Wayne Linton OCP, I.S.P.

● Over 40 years in IT● More than half that as an Oracle DBA● 35 years at Shell Canada Limited● SAIT Instructor● Past-President COUG● Presenter at OOW, Oracle Days, COUG● Published in Oracle Magazine, Select Journal

(... and I enjoy photography)

● Established 1999● Remote and on-site DBA support● Application Express Design/Development● Training● Clients in Canada and the U.S.

Why do this?

● Companies may have a number of databases on different platforms and DBMS offerings

● Vendor software might only run on MSSQL● Want a central 'truth' of data to pull from● Want a central warehouse to represent all data● Connect ODBC-compliant databases

Open Database Connectivity

● OS independent, vendor neutral API● Mainly used to access Databases via SQL● Built in early '90s by Microsoft, in concert with

Oracle, Apple, Sun, DEC, Sybase, Tandem, Lotus and others – ISO Standard

● Unix community picked up ODBC when MS moved its focus to OLE-DB

(JDBC is java equivalent )

ODBC

● Commonly used in Windows with Excel and Access database

● OS provides driver manager (unixODBC)● DBMS driver typically supplied by vendor● Vendor drivers available at cost such as:

● Oracle gateway products (dg4msql)● easysoft ● DataDirect

–

ODBC Driver

● Translation layer between SQL and DBMS● Large subset of standard SQL functionality● 3rd Party vendors sell “better” drivers● Available for Oracle, MySQL, MSSQL, DB2,

Progress, Sybase, etc.● Some even work on csv flat-files

ODBC Driver Manager

● Delivered with OS● Loads ODBC Driver appropriate to DBMS data

source● Free Open Source implementation on 'nix

systems - unixODBC

SQL Server Driver

● Released in the spring of 2012● Available on 64-bit Linux v5 or v6 only● Free to use● SQL Server 2008 R2, and SQL Server 2012● Download at:

Microsoft® SQL Server® ODBC Driver 1.0 for Linux

Demo Environment

● Laptop, 8gb, 64-bit, Windows 7● VirtualBox, Win7, SQL Server 2012 (PC7C)● VirtualBox, CentOS 5.8, 64-bit, Oracle

11.2.0.3EE, 11gXE (PC6VB2)

SQL Server (PC7C)

ODBC Driver/opt/microsoft/sqlncli/lib64/libsqlncli-11.0.so.1790.0

/etc/odbcinst.ini

ODBC ManagerunixODBC v2.3.0

/etc/odbc.ini

TCP/IP

sqlcmd

Oracle

Oracle Net

HS

dg4odbc

SQL*Plusselect * from <tab>@<alias>

isql

(PC6VB2)

● Database Gateway For ODBCOracle® Database Gateway for ODBC User's Guide 11g Release 2 (11.2)

● Comes installed with database$ORACLE_HOME/hs/lib/dg4odbc.o

● Connects Oracle to ODBC via Heterogeneous Services (HS)

Oracle® Database Heterogeneous Connectivity User’s Guide11g Release 2 (11.2)Oracle® Database Gateway Installation and Configuration Guide

● Other gateways available for cost (dg4mssql)

Oracle

Oracle Net

HS

dg4odbc

SQL*Plusselect * from <tab>@<alias>

Installation – Driver Manager

● Download the MS SQL Server ODBC file(detailed instructions on the download site)– Login as root

– tar xvf sqlncli-11.0.1790.0.tar.gz

– yum remove unixODBC

– cd ./sqlncli-11.0.1790.0

– ./build_dm.sh (this will download unixODBC v2.3.0)

Installation – ODBC Driver

● Still logged in as root ....

– cd ./sqlncli-11.0.1790.0– ./install.sh verify– ./install.sh install– odbcinst -q -d -n "SQL Server Native Client 11.0"

● Test the driver against the SQL Server database:

sqlcmd -S<ip address> -U<user> -P<password>-Q”select * from information_schema.schemata”

SQL Server (PC7C)

ODBC Driver/opt/microsoft/sqlncli/lib64/libsqlncli-11.0.so.1790.0

/etc/odbcinst.ini

ODBC ManagerunixODBC v2.3.0

/etc/odbc.ini

TCP/IP

sqlcmd isql

(PC6VB2)

Configure odbcinst.ini

● Defines the ODBC Driver settings● Should be created by the install process● /etc/odbcinst.ini

[SQL Server Native Client 11.0]Description=Microsoft SQL Server ODBC Driver V1.0 for LinuxDriver=/opt/microsoft/sqlncli/lib64/libsqlncli-11.0.so.1790.0Threading=1UsageCount=1

Configure odbc.ini

● Defines Data Source Name connection ● /etc/odbc.ini (local ~/.odbc.ini)

[<dsn>]Driver = SQL Server Native Client 11.0Server = tcp:<mssql hostname or IP address>,1433

● Test the odbc settings:isql <dsn> <user> <passwd>select * from information_schema.schemata;quit;

SQL Server (PC7C)

ODBC Driver/opt/microsoft/sqlncli/lib64/libsqlncli-11.0.so.1790.0

/etc/odbcinst.ini

ODBC ManagerunixODBC v2.3.0

/etc/odbc.ini

TCP/IP

sqlcmd

Oracle

Oracle Net

HS

dg4odbc

SQL*Plusselect * from <tab>@<alias>

isql

(PC6VB2)

● Configure HS in $ORACLE_HOME/hs/admin● Filename init<dsn>.ora (case matters!)

# Database Gateway for ODBC## HS init parameters#HS_FDS_CONNECT_INFO = <dsn>HS_FDS_SHAREABLE_NAME = /usr/lib64/libodbc.soHS_LANGUAGE=AMERICAN_AMERICA.WE8ISO8859P15HS_FDS_PROC_IS_FUNC = TRUEHS_FDS_RESULTSET_SUPPORT = TRUE# Environment variables required for the non-Oracle system#set LD_LIBRARY_PATH=/opt/microsoft/sqlncli/lib64:/usr/lib64:

/u01/app/oracle/product/11.2.0/dbhome_1/lib##HS_FDS_TRACE_LEVEL = debug

Oracle

Oracle Net

HS

dg4odbc

SQL*Plusselect * from <tab>@mssql

● Connection to database HS is done via Oracle Net

● Oracle Listener configured like:(SID_DESC =

(ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1) (SID_NAME = <dsn>) (PROGRAM = dg4odbc) (ENVS = "LD_LIBRARY_PATH=/opt/microsoft/sqlncli/lib64:/usr/lib64:

/u01/app/oracle/product/11.2.0/dbhome_1/lib")

)

Oracle

Oracle NetHS

dg4odbc

SQL*Plusselect * from <tab>@<alias>

Bounce the listener ...

● Tnsnames entry such as:<alias> = (DESCRIPTION = (ADDRESS = (PROTOCOL = TCP) (HOST = <oracle db host>) (PORT = 1521)) (CONNECT_DATA = (SID = <dsn>)) (HS = OK)

Oracle

Oracle Net

HS

dg4odbc

SQL*Plus

select * from <tab>@<alias>

... one last step

Database Link

create public database link <dblink>connect to <user> identified by <pswd>using '<alias>';

● You can not connect directly to SQL Server via Oracle Net

... now we are ready to go!

Demos ...

● isql, sqlcmd● DML and some functions● DDL handling● HS views● V$ views

HS Data Dictionary Views

Dynamic Performance Views

● V$HS_PARAMETER● V$HS_SESSION● V$HS_AGENT

Some Gotchas

● DDL● Datatype conversion issues● Special variables like SYSDATE● Date arithmetic, different functions● Optimizer statistics, execution plans● No rowid

Summary

● ODBC-compliant databases can exchange data● Free drivers available● Doesn't do everything, but probably 'good

enough'!● Viable solution for bringing in data from other

sources into one central database/warehouse

(oh, and yes it works with 11gXE)

Questions?

Accessing SQL Server Data

from Oracle on Linux

for FREE!

COUG

15-NOV-2012

Wayne Lintonwayne.linton@oradba.ca