数据的装载:
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