在执行如下命令时,需要首先在客户端运行中输入db2cmd进行初始化或者su到db2的实例下操作。
在执行如下命令时,需要首先在客户端运行中输入db2cmd进行初始化或者su到db2的实例下操作。
一、常识性命令
1、db2 connect to --连接到本地数据库名
db2 connect to user using --连接到远端数据库
2、 db2 force application all --强迫所有应用断开数据库连接
3、db2 backup db db2name --备份整个数据库数据
db2 restore db
4、db2 list application --查看所有连接(需要连接到具体数据库才能查看)
5、db2stop --停止数据库 db2start --启动数据库
6、create database using codeset utf-8 territory CN --创建数据库使用utf-8编码
7、db2 catalog 命令
db2 catalog tcpip node remote server --把远程数据库映射到本地接点一般为50000
db2 catalog db as at node PUB11 --远程数据库名称到本地接点
db2 CONNECT TO user using --连接本地接点访问远程数据库
8、数据库导出
db2look -d -u -e -o .sql --导出数据库的表结构,其中用户空间一般为
db2admin/db2inst2
db2look -d -u -t -e -o .sql --导出数据库中表1和表2的表结构
db2move export --导出数据库数据
db2move export -tn , --导出数据库中表和表数据
9、数据库导入
db2 -tvf .sql --把上述导出的表结构导入到数据库表结构
db2move load -lo replace --把上述“db2move export “导出的数据导入到数据库中并把相同的数据替换掉
在实际使用过程中,如果用到db2自增主键,需要使用by default, 而不是always,,功能是一样的,但这样在数据移植时候会很方便!
10、db2 connect reset 或 db2 terminate --断开与数据库的连接
11、db2set db2codepage=1208 --修改页编码为1208
12、db2 describe table --查看表结构
13、db2 list tables --查看数据库中所有表结构
db2 list tables for system --列出所有系统表
14、db2 list tablespaces --列出表空间
15、fetch first 10 rows only --列出表中前10条数据
例如:select * from fetch first 10 rows only
16、coalesce(字段名,转换后的值) --对是null的字段进行值转换
例如:select coalesce(id,1) from --对表中id如果为null转换成1
二、导入数据:
1、 以默认分隔符加载,默认为“,”号
db2 "import from btpoper.txt of del insert into btpoper"
2、 以指定分隔符“|”加载
db2 "import from btpoper.txt of del modified by coldel| insert into btpoper"
三、卸载数据:
1、 卸载一个表中全部数据
db2 "export to btpoper.txt of del select * from btpoper"
db2 "export to btpoper.txt of del modified by coldel| select * from btpoper"
2、 带条件卸载一个表中数据
db2 "export to btpoper.txt of del select * from btpoper where brhid='907020000'"
db2 "export to cmmcode.txt of del select * from cmmcode where codtp='01'"
db2 "export to cmmcode.txt of del modified by coldel| select * from cmmcode where codtp='01'"
四、查询数据结构及数据:
db2 "select * from btpoper"
db2 "select * from btpoper where brhid='907020000' and oprid='0001'"
db2 "select oprid,oprnm,brhid,passwd from btpoper"
五、删除表中数据:
db2 "delete from btpoper"
db2 "delete from btpoper where brhid='907020000' or brhid='907010000'"
六、修改表中数据:
db2 "update svmmst set prtlines=0 where brhid='907010000' and jobtp='02'"
db2 "update svmmst set prtlines=0 where jobtp='02' or jobtp='03'"
七、联接数据库
db2 connect to btpdbs
八、清除数据库联接
db2 connect reset 断开数据库连接
db2 terminate 断开数据库连接
db2 force applications all 断开所有数据库连接
九、备份数据库
1、 db2 backup db btpdbs
2、 db2move btpdbs export
db2look -d btpdbs -e -x [-a] -o crttbl.sql

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