7. Oracle数据加载和卸载

  在日常工作中;经常会遇到这样的需求:

    • Oracle 数据表跟文本或者文件格式进行交互;即将指定文件内容导入对应的 Oracle 数据表中;或者从 Oracle 数据表导出。
    • 其他数据库中的表跟Oracle数据库进行交互。

  若是少量数据;可选择的解决方案有很多。常用的用 Pl/SQL developer工具,或者手动转换为 INSERT 语句,或者通过API。但数据量大;用上面的方法效率太烂了。本文来说说 Oracle 数据的加载和卸载。

    • Oracle中的DBLINK
    • Oracle加载数据-外部表
    • Oracle加载数据-sqlldr工具
    • Oracle卸载数据-sqludr

一. Oracle 中的 DBLINK

  在日常工作中;会遇到不同的数据库进行数据对接;每个数据库都有着功能;像Oracle有 DBLINK ; PostgreSQL有外部表。

1.1 Oracle DBlink 语法

CREATE [PUBLIC] DATABASE LINK link
CONNECT TO username
IDENTIFIED BY password
USING 'connectstring'

1.2 Oracle To Mysql

  在oracle配置mysql数据库的dblink

二.Oracle加载数据-外部表

  ORACLE外部表用来存取数据库以外的文本文件(Text File)或ORACLE专属格式文件。因此,建立外部表时不会产生段、区、数据块等存储结构,只有与表相关的定义放在数据字典中。外部表,顾名思义,存储在数据库外面的表。当存取时才能从ORACLE专属格式文件中取得数据,外部表仅供查询,不能对外部表的内容进行修改(INSERT、UPDATE、DELETE操作)。不能对外部表建立索引。

2.1 创建外部表需要的目录

# 创建外部表需要的目录
SQL> create or replace directory DUMP_DIR as '/data/ora_ext_lottu'; Directory created.
# 给用户授予指定目录的操作权限
SQL> GRANT READ,WRITE ON DIRECTORY DUMP_DIR TO lottu; Grant succeeded.

2.2 外部表源文件lottu.txt

,ACCOUNTING,NEW YORK
,RESEARCH,DALLAS
,SALES,CHICAGO
,OPERATIONS,BOSTON

2.3 创建外部表

drop table dept_external purge;

CREATE TABLE dept_external (
deptno NUMBER(),
dname VARCHAR2(),
loc VARCHAR2()
)
ORGANIZATION EXTERNAL
(TYPE oracle_loader
DEFAULT DIRECTORY DUMP_DIR
ACCESS PARAMETERS
(
RECORDS DELIMITED BY newline
BADFILE 'lottu.bad'
LOGFILE 'lottu.log'
FIELDS TERMINATED BY "," OPTIONALLY ENCLOSED BY '"'
(
deptno INTEGER EXTERNAL(),
dname CHAR(),
loc CHAR()
)
)
LOCATION ('lottu.txt')
)
REJECT LIMIT UNLIMITED;

查看数据

SQL> select * from dept_external;

    DEPTNO DNAME  LOC
---------- -------------------- -------------------------
10 ACCOUNTING NEW YORK
20 RESEARCH DALLAS
30 SALES CHICAGO
40 OPERATIONS BOSTON

三. Oracle加载数据-sqlldr工具

3.1 准备实验对象

  创建文件lottu.txt;和表tbl_load_01。

[oracle@oracle235 ~]$ seq 1000|awk -vOFS="," '{print $1,"lottu",systime()-$1}' > lottu.txt
[oracle@oracle235 ~]$ sqlplus lottu/li0924 SQL*Plus: Release 11.2.0.4.0 Production on Mon Aug 13 22:58:34 2018 Copyright (c) 1982, 2013, Oracle. All rights reserved. Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options SQL> create table tbl_load_01 (id number,name varchar2(10),accountid number); Table created.

3.2 创建控制文件lottu.ctl

load data
characterset utf8
infile '/home/oracle/lottu.txt'
truncate into table tbl_load_01
fields terminated by ','
trailing nullcols
optionally enclosed by ' ' TRAILING NULLCOLS
(
id ,
name,
accountid
)

3.3 执行sqlldr

[oracle@oracle235 ~]$ sqlldr 'lottu/"li0924"' control=/home/oracle/lottu.ctl log=/home/oracle/lottu.log bad=/home/oracle/lottu.bad

SQL*Loader: Release 11.2.0.4.0 - Production on Mon Aug 13 23:10:12 2018

Copyright (c) 1982, 2011, Oracle and/or its affiliates.  All rights reserved.

Commit point reached - logical record count 64
Commit point reached - logical record count 128
Commit point reached - logical record count 192
Commit point reached - logical record count 256
Commit point reached - logical record count 320
Commit point reached - logical record count 384
Commit point reached - logical record count 448
Commit point reached - logical record count 512
Commit point reached - logical record count 576
Commit point reached - logical record count 640
Commit point reached - logical record count 704
Commit point reached - logical record count 768
Commit point reached - logical record count 832
Commit point reached - logical record count 896
Commit point reached - logical record count 960
Commit point reached - logical record count 1000

四.Oracle卸载数据-sqludr

  sqludr是将Oracle数据表导出到文本中;是牛人楼方鑫开发的。并非Oracle自带工具;需要下载安装才能使用。

4.1 sqludr安装

[oracle@oracle235 ~]$ unzip sqluldr2linux64.zip
Archive: sqluldr2linux64.zip
inflating: sqluldr2linux64.bin
[oracle@oracle235 ~]$ mv sqluldr2linux64.bin $ORACLE_HOME/bin/sqludr

4.2 查看sqludr帮助

[oracle@oracle235 ~]$ sqludr -?

SQL*UnLoader: Fast Oracle Text Unloader (GZIP, Parallel), Release 4.0.
(@) Copyright Lou Fangxin (AnySQL.net) - , all rights reserved. License: Free for non-commercial useage, else USD per server. Usage: SQLULDR2 keyword=value [,keyword=value,...] Valid Keywords:
user = username/password@tnsname
sql = SQL file name
query = select statement
field = separator string between fields
record = separator string between records
rows = print progress for every given rows (default, )
file = output file name(default: uldrdata.txt)
log = log file name, prefix with + to append mode
fast = auto tuning the session level parameters(YES)
text = output type (MYSQL, CSV, MYSQLINS, ORACLEINS, FORM, SEARCH).
charset = character set name of the target database.
ncharset= national character set name of the target database.
parfile = read command option from parameter file for field and record, you can use '0x' to specify hex character code,
\r=0x0d \n=0x0a |=0x7c ,=0x2c, \t=0x09, :=0x3a, #=0x23, "=0x22 '=0x27

4.3 执行sqludr

[oracle@oracle235 ~]$ sqludr lottu/li0924 query="tbl_load_01" file=lottu01.txt field=","
rows exported at -- ::, size MB.
rows exported at -- ::, size MB.
output file lottu01.txt closed at rows, size MB.
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