数据库的表备份与恢复

把数据导入到指定的文件：
table expression
into outfile ‘filename‘ <选项名称> |
into dumpfile ‘filename‘ |
into <user variable> <,....>
<选项名称>： fields [terminated by [literal] ] ....
	     lines terminated by <literal>
as:
select *
from test
into outfile ‘test.txt‘
把test 数据导入到 test.txt文件，在linux 下，test.txt和test表的存放位置相同
默认值中：fields terminated by ‘\t‘  lines terminated by ‘\n‘enclosed by ‘‘escapsed by ‘\\‘
as:
select *
from test
into outfile ‘test.txt‘
fields terminated by ‘,‘
lines terminated by ‘?‘
表示导出的数据中，字段之间用 ‘,‘分隔，行之间用 ‘?‘分隔

as:
select *
from test
into outfile ‘test.txt‘
fields terminated by ‘,‘
optionally enclosed by ‘"‘
lines terminated by ‘?‘
表示字符是用 ‘"‘包围的，如果全部用‘"‘包围，则不用加上 optionally

也可用dumpfile,但是所有行彼此挨着，值与行之间没有任何标志
as:
select *
from test
into dumpfile ‘test.dump‘

载入数据数据表中
load data [low_priority][concurrent][local]
infile ‘filename‘
[replace]
into table tablename
[fields terminated by literal]
[lines terminated by literal]
as:
load data infile ‘test.txt‘
replace
into table test;

as:
load data infile ‘test.txt‘
replace
into table test
fields terminated by ‘,‘
line terminated by ‘?‘