数据转载

oracle228

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数据转载

数据的装载:

•SQL*LOADER

•外部表

•导入/导出

SQL*LOADER:

SQL*LOADER是一个ORACLE工具，能够将数据从外部数据文件装载到数据库中。

运行SQL*LOADER的命令是sqlldr。

Sqlldr的两种使用方式：

1. 只使用一个控制文件，在这个控制文件中包含数据

2. 使用一个控制文件(作为模板) 和一个数据文件

一般采用第二种方式，数据文件可以是 CSV 文件、txt文件或者以其他分割符分隔的。

说明：操作类型 可用以下中的一值：
1) insert --为缺省方式，在数据装载开始时要求表为空
2) append --在表中追加新记录
3) replace --删除旧记录(用 delete from table 语句)，替换成新装载的记录
4) truncate --删除旧记录(用 truncate table 语句)，替换成新装载的记录

通过spool来制作数据文件：--可以查询帮助文档的示例代码

SQL> spool /u01/app/oracle/test_data_loader/student.txt--开启spool导出数据文件
SQL> select id ||',' || name ||',' || age ||',' || inner_date from student;--导出数据

ID||','||NAME||','||AGE||','||INNER_DATE
--------------------------------------------------------------------------------
1,zhangsan,21,23-JAN-15
2,lisi,22,23-JAN-15
3,wangwu,23,23-JAN-15

SQL> spool off;--关闭
SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@localhost test_data_loader]$ cat student.txt--可以查看到导出的数据记录
SQL> select id ||',' || name ||',' || age ||',' || inner_date from student;

ID||','||NAME||','||AGE||','||INNER_DATE
--------------------------------------------------------------------------------
1,zhangsan,21,23-JAN-15
2,lisi,22,23-JAN-15
3,wangwu,23,23-JAN-15

SQL> spool off;

写配置文件：
[oracle@localhost test_data_loader]$ vi student.ctl
[oracle@localhost test_data_loader]$ cat student.ctl
options(skip=4)--表示前面的四行
load data--导入数据
infile 'student.txt'--通过该文件导入数据
into table student--导入的表
insert--执行的是插入操作
fields terminated by ','--记录中的分割符
(
id char,--注意虽然表中是number类型，但是要写char类型
name char,
age char,
inner_date date nullif (inner_date = "null"))
[oracle@localhost test_data_loader]$

既然是insert操作所以：
SQL> truncate table student;--清空表，由于执行的是插入操作

Table truncated.

SQL> select * from student;

no rows selected

执行sqlldr操作：
[oracle@localhost test_data_loader]$ sqlldr hr/hr control= student.ctl log = student.log

SQL*Loader: Release 11.2.0.1.0 - Production on Fri Jan 23 23:11:08 2015

Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.

Commit point reached - logical record count 4
[oracle@localhost test_data_loader]$ cat student.log

SQL*Loader: Release 11.2.0.1.0 - Production on Fri Jan 23 23:11:08 2015

Copyright (c) 1982, 2009, Oracle and/or its affiliates. All rights reserved.

Control File: student.ctl
Data File: student.txt
Bad File: student.bad
Discard File: none specified

(Allow all discards)

Number to load: ALL
Number to skip: 4
Errors allowed: 50
Bind array: 64 rows, maximum of 256000 bytes
Continuation: none specified
Path used: Conventional

Table STUDENT, loaded from every logical record.
Insert option in effect for this table: INSERT

Column Name Position Len Term Encl Datatype
------------------------------ ---------- ----- ---- ---- ---------------------
ID FIRST * , CHARACTER
NAME NEXT * , CHARACTER
AGE NEXT * , CHARACTER
INNER_DATE NEXT * , DATE DD-MON-RR
NULL if INNER_DATE = 0X6e756c6c(character 'null')

Record 4: Rejected - Error on table STUDENT, column ID.
Column not found before end of logical record (use TRAILING NULLCOLS)

Table STUDENT:
3 Rows successfully loaded.
1 Row not loaded due to data errors.
0 Rows not loaded because all WHEN clauses were failed.
0 Rows not loaded because all fields were null.


Space allocated for bind array: 66048 bytes(64 rows)
Read buffer bytes: 1048576

Total logical records skipped: 4
Total logical records read: 4
Total logical records rejected: 1
Total logical records discarded: 0

Run began on Fri Jan 23 23:11:08 2015
Run ended on Fri Jan 23 23:11:08 2015

Elapsed time was: 00:00:00.10
CPU time was: 00:00:00.01
[oracle@localhost test_data_loader]$ sqlplus hr/hr

SQL*Plus: Release 11.2.0.1.0 Production on Fri Jan 23 23:13:14 2015

Copyright (c) 1982, 2009, Oracle. All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> select * from student;

ID NAME AGE INNER_DATE
---------- -------------------- ---------- ------------
1 zhangsan 21 23-JAN-15
2 lisi 22 23-JAN-15
3 wangwu 23 23-JAN-15

SQL> exit

外部表：

外部表中的数据不装入数据库中，数据库中只存储外部表的定义信息，实际的数据位于操作系统的平面文件中，

但是，可以在数据库中，像访问正常表那样，通过select语句来访问操作系统中的平面文件中所含有的数据。

外部表是只读的。

可以使用SQL，PL/SQL和JAVA访问外部表。

外表表分为2种：使用数据泵引擎生成的外部表、

SQL>create table student_re(re_id,re_name,re_age,re_inner_date)
organization external
(
type oracle_datapump--外部表生成方式是数据泵
default directory test_impdp_expdp--默认的路径
location('student.dmp')--通过路径和文件名生成外部表在操作系统的平面数据文件
)
parallel--并行
as
select * from student; 2 3 4 5 6 7 8 9 10

Table created.

SQL> !ls
student.dmp STUENT_17109.log
SQL> select * from stuent;

RE_ID RE_NAME RE_AGE RE_INNER_DAT
---------- -------------------- ---------- ------------
1 zhangsan 21 23-JAN-15
2 lisi 22 23-JAN-15
3 wangwu 23 23-JAN-15

SQL>

根据文本文件创建的外部表。

SQL> spool student.txt

ID||','||NAME||','||AGE||','||INNER_DATE
--------------------------------------------------------------------------------
1,zhangsan,21,23-JAN-15
2,lisi,22,23-JAN-15
3,wangwu,23,23-JAN-15

SQL> exit
Disconnected from Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
[oracle@localhost test_impdp_expdp]$ vi student.txt
[oracle@localhost test_impdp_expdp]$ sqlplus hr/hr

SQL*Plus: Release 11.2.0.1.0 Production on Sat Jan 24 00:05:18 2015

Copyright (c) 1982, 2009, Oracle. All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options

SQL> create table student_re_2--该外部表的名称下面列是外部表的建表语句，而上面通过数据泵的表是通过as select from tab来建立的。
2 (id number,name varchar2(20),age number(10),inner_date date)
3 organization external
4 ( type oracle_loader--外部文件方式
5 default directory test_impdp_expdp--默认的目录
6 access parameters--访问外部文件所遵守的格式
7 (
records delimited by newline--记录分隔符
fields terminated by ','--字段分隔符
8 ) location ('student.txt')--位置
); 9 10 11

Table created.

SQL> select * from student_re_2;

ID NAME AGE INNER_DATE
---------- -------------------- ---------- ------------
1 zhangsan 21 23-JAN-15
2 lisi 22 23-JAN-15
3 wangwu 23 23-JAN-15

SQL>