ImpalaのODBCドライバを利用して、Impalaに対してクエリ実行のリクエストを送信することができます。
ImpalaのODBCドライバの入手とインストール方法については、Cloudera社のWebページ等を参照してください。
以下は、unixODBCパッケージを利用し、スレーブサーバ slave6 に対してクエリ実行(SELECT)をリクエストする際の実行例です。
unixODBCパッケージ、unixODBC-develパッケージのインストール
# yum install unixODBC unixODBC-devel <Enter> Loaded plugins: product-id, security, subscription-manager ・・省略・・ Complete! # odbcinst -j <Enter> 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 #
ImpalaのODBCドライバのインストール
# rpm -ivh /tmp/ClouderaImpalaODBC-2.5.22.1023-1.el6.x86_64.rpm <Enter> 準備中... ########################################### [100%] 1:ClouderaImpalaODBC ########################################### [100%] #
/etc/odbc.ini の設定
# cp -p /opt/cloudera/impalaodbc/Setup/odbc.ini /etc/odbc.ini <Enter> # /etc/odbc.iniの編集（接続先ホスト名とポート番号を編集） # cat /etc/odbc.ini <Enter> [ODBC] # Specify any global ODBC configuration here such as ODBC tracing. [ODBC Data Sources] Sample Cloudera Impala DSN 64=Cloudera ODBC Driver for Impala 64-bit [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=slave6 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=10000 SocketTimeout=0 StringColumnLength=32767 UseNativeQuery=0
/etc/cloudera.impalaodbc.iniの設定
# cp /opt/cloudera/impalaodbc/lib/64/cloudera.impalaodbc.ini /etc/cloudera.impalaodbc.ini <Enter> # /etc/cloudera.impalaodbc.iniの編集（使用するライブラリの指定） # cat /etc/cloudera.impalaodbc.ini <Enter> [Driver] ## - Note that this default DriverManagerEncoding of UTF-32 is for iODBC. ## - unixODBC uses UTF-16 by default. ## - If unixODBC was compiled with -DSQL_WCHART_CONVERT, then UTF-32 is the correct value. ## Execute 'odbc_config --cflags' to determine if you need UTF-32 or UTF-16 on unixODBC ## - SimbaDM can be used with UTF-8 or UTF-16. ## The DriverUnicodeEncoding setting will cause SimbaDM to run in UTF-8 when set to 2 or UTF-16 when set to 1. DriverManagerEncoding=UTF-32 ErrorMessagesPath=/opt/cloudera/impalaodbc/ErrorMessages/ LogLevel=0 LogPath= ## - Uncomment the ODBCInstLib corresponding to the Driver Manager being used. ## - Note that the path to your ODBC Driver Manager must be specified in LD_LIBRARY_PATH (LIBPATH for AIX). ## - Note that AIX has a different format for specifying its shared libraries. # Generic ODBCInstLib # iODBC #ODBCInstLib=libiodbcinst.so # SimbaDM / unixODBC ODBCInstLib=libodbcinst.so # AIX specific ODBCInstLib # iODBC #ODBCInstLib=libiodbcinst.a(libiodbcinst.so.2) # SimbaDM #ODBCInstLib=libodbcinst.a(odbcinst.so) # unixODBC #ODBCInstLib=libodbcinst.a(libodbcinst.so.1)
環境変数の設定
# export LD_LIBRARY_PATH=/usr/local/lib:/opt/cloudera/impalaodbc/lib/64 <Enter> # export CLOUDERAIMPALAINI=/etc/cloudera.impalaodbc.ini <Enter>
クエリ実行
# isql -v impalaodbc <Enter> +---------------------------------------+ | Connected! | | | | sql-statement | | help [tablename] | | quit | | | +---------------------------------------+ SQL> select * from example_table1 <Enter> +-------+------------------+------------+-----------------+-------------------------+ | id | str_column | bool_column| double_column | date_column | +-------+------------------+------------+-----------------+-------------------------+ | 1 | 文字列1 | 1 | 101.2 | 2013-10-24 10:20:05 | | 2 | 文字列2 | 0 | 53.15 | 2013-10-25 10:20:05 | | 3 | 文字列3 | 1 | -18.5 | 2013-10-26 10:20:05 | | 4 | 文字列4 | 0 | 0 | 2013-10-27 10:20:05 | | 5 | 文字列5 | 1 | -12.35 | 2013-10-28 10:20:05 | +-------+------------------+------------+-----------------+-------------------------+ SQLRowCount returns -1 5 rows fetched SQL> <Enter>
