本文详细讲解了CentOS-6.5-x86_64环境下 Impala ODBC的安装和使用。
rpm -qa|grep unixODBC
如果没有安装，使用下面的命令安装：
yum install unixODBCyum install unixODBC-devel
使用odbcinst命令查看unixODBC配置文件路径，不同版本的unixODBC配置文件路径是不同的，如果是源代码方式安装unixODBC，也可以通过编译参数--sysconfdir指定。
[root@h1 ~]# odbcinst -j unixODBC 2.2.14 DRIVERS............: /etc/odbcinst.ini SYSTEM DATA SOURCES: /etc/odbc.ini FILE DATA SOURCES..: /etc/ODBCDataSources USER DATA SOURCES..: /root/.odbc.ini SQLULEN Size.......: 8 SQLLEN Size........: 8 SQLSETPOSIROW Size.: 8
下载ClouderaImpalaODBC-2.5.15.1015-1.el6.x86_64.rpm，保存到：/home/soft 目录，并进行安装：
[root@h1 soft]# ll total 16232 -rw-r--r--. 1 root root 16619934 Aug 24 06:37 ClouderaImpalaODBC-2.5.15.1015-1.el6.x86_64.rpm [root@h1 soft]# rpm -ivh ClouderaImpalaODBC-2.5.15.1015-1.el6.x86_64.rpm Preparing... ########################################### [100%] 1:ClouderaImpalaODBC ########################################### [100%] [root@h1 soft]#
[root@h1 impalaodbc]# pwd /opt/cloudera/impalaodbc [root@h1 impalaodbc]# ll total 1016 -rwxr-xr-x. 1 root root 1007048 Apr 21 12:21 Cloudera ODBC Driver for Impala Install Guide.pdf -rwxr-xr-x. 1 root root 12003 Apr 21 12:21 Cloudera-EULA.txt drwxr-xr-x. 3 root root 4096 Aug 24 07:15 ErrorMessages -rwxr-xr-x. 1 root root 3261 Apr 21 12:21 Readme.txt -rwxr-xr-x. 1 root root 2350 Apr 21 12:21 Release Notes.txt drwxr-xr-x. 2 root root 4096 Aug 24 07:15 Setup drwxr-xr-x. 3 root root 4096 Aug 24 07:15 lib [root@h1 impalaodbc]#
设置驱动的环境变量：
在 /etc/profile 最后添加：
export LD_LIBRARY_PATH=/usr/local/lib:/opt/cloudera/impalaodbc/lib/64
然后执行：source /etc/profile
使修改的脚本立即生效。
拷贝：cloudera.impalaodbc.ini 到 /etc/目录：
[root@h1 Setup]# pwd /opt/cloudera/impalaodbc/Setup [root@h1 Setup]# cp cloudera.impalaodbc.ini /etc/ [root@h1 Setup]#
# Generic ODBCInstLib # iODBC #ODBCInstLib=libiodbcinst.so # SimbaDM / unixODBC ODBCInstLib=libodbcinst.so
也就是说不使用iODBC , 使用 unixODBC
参照 /opt/cloudera/impalaodbc/Setup/odbc.ini ,修改：/etc/odbc.ini 文件。修改后的odbc.ini如下：
[impalaodbc] # Description: DSN Description. # This key is not necessary and is only to give a description of the data source. Description=Cloudera ODBC Driver for Impala (64-bit) DSN # Driver: The location where the ODBC driver is installed to. Driver=/opt/cloudera/impalaodbc/lib/64/libclouderaimpalaodbc64.so # The DriverUnicodeEncoding setting is only used for SimbaDM # When set to 1, SimbaDM runs in UTF-16 mode. # When set to 2, SimbaDM runs in UTF-8 mode. #DriverUnicodeEncoding=2 # Values for HOST, PORT, KrbFQDN, and KrbServiceName should be set here. # They can also be specified on the connection string. HOST=172.16.230.152 PORT=21050 Database=default # The authentication mechanism. # 0 - no authentication. # 1 - Kerberos authentication # 2 - Username authentication. # 3 - Username/password authentication. # 4 - Username/password authentication with SSL. AuthMech=0 # Kerberos related settings. KrbFQDN= KrbRealm= KrbServiceName= # Username/password authentication with SSL settings. UID= PWD= CAIssuedCertNamesMismatch=1 TrustedCerts=/opt/cloudera/impalaodbc/lib/64/cacerts.pem # Specify the proxy user ID to use. #DelegationUID= # General settings TSaslTransportBufSize=1000 RowsFetchedPerBlock=1000 SocketTimeout=0 StringColumnLength=32767 UseNativeQuery=0
执行 isql -v impalaodbc
[root@h1 ~]# isql -v impalaodbc +---------------------------------------+ | Connected! | | | | sql-statement | | help [tablename] | | quit | | | +---------------------------------------+ SQL> select * from tab1; [S1000][unixODBC][Cloudera][ImpalaODBC] (110) Error while executing a query in Impala: [HY000] : Error: Error: could not match input [ISQL]ERROR: Could not SQLPrepare SQL> select * from tab1 +------------+------+-------------------------+------------------------------+ | id | col_1| col_2 | col_3 | +------------+------+-------------------------+------------------------------+ | 1 | 1 | 123.123 | 2012-10-24 08:55:00 | | 2 | 0 | 1243.5 | 2012-10-25 13:40:00 | | 3 | 0 | 24453.325 | 2008-08-22 09:33:21.123000000| | 4 | 0 | 243423.325 | 2007-05-12 22:32:21.334540000| | 5 | 1 | 243.325 | 1953-04-22 09:11:33 | +------------+------+-------------------------+------------------------------+ SQLRowCount returns -1 5 rows fetched注意：执行的sql最后不要加封号。
这样配置后，C/C++程序就可以通过unixODBC访问Impala中的数据了。
默认安装的Impala ODBC是评估版的，需要购买license，参见安装文档 Cloudera ODBC Driver for Impala Install Guide.pdf 中的这样一段话：
If you are installing a driver with an evaluation license and you have purchased a perpetual license, then copy the License.lic file you received via e-mail into the /opt/cloudera/impalaodbc/lib/32 or /opt/cloudera/impalaodbc/lib/64 folder, depending on the version of the driver you installed.
评估时为多长时间，目前还没找到答案。或者让你一直评估吧：）
原创作品，转载请注明出处
http://blog.csdn.net/yangzhaohui168/article/details/38800803
原文地址：http://blog.csdn.net/yangzhaohui168/article/details/38800803
