一、Mongodb導出工具mongoexport
Mongodb中的mongoexport工具可以把一個collection導出成JSON格式或CSV格式的文件?？梢酝ㄟ^參數指定導出的數據項，也可以根據指定的條件導出數據。
mongoexport具體用法
- [root@localhost mongodb]# ./bin/mongoexport --help
- Export MongoDB data to CSV, TSV or JSON files.
- options:
- --help produce help message
- -v [ --verbose ] be more verbose (include multiple times for more
- verbosity e.g. -vvvvv)
- --version print the program's version and exit
- -h [ --host ] arg mongo host to connect to ( <set name>/s1,s2 for
- sets)
- --port arg server port. Can also use --host hostname:port
- --ipv6 enable IPv6 support (disabled by default)
- -u [ --username ] arg username
- -p [ --password ] arg password
- --dbpath arg directly access mongod database files in the given
- path, instead of connecting to a mongod server -
- needs to lock the data directory, so cannot be used
- if a mongod is currently accessing the same path
- --directoryperdb if dbpath specified, each db is in a separate
- directory
- --journal enable journaling
- -d [ --db ] arg database to use
- -c [ --collection ] arg collection to use (some commands)
- -f [ --fields ] arg comma separated list of field names e.g. -f
- name,age
- --fieldFile arg file with fields names - 1 per line
- -q [ --query ] arg query filter, as a JSON string
- --csv export to csv instead of json
- -o [ --out ] arg output file; if not specified, stdout is used
- --jsonArray output to a json array rather than one object per
- line
- -k [ --slaveOk ] arg (=1) use secondaries for export if available, default
- true
參數說明
-h:指明數據庫宿主機的IP
-u:指明數據庫的用戶名
-p:指明數據庫的密碼
-d:指明數據庫的名字
-c:指明collection的名字
-f:指明要導出那些列
-o:指明到要導出的文件名
-q:指明導出數據的過濾條件
二、常用數據導出實例
1.直接導出數據到文件中
[root@localhost bin]# ./mongoexport -d my_mongodb -c user -o user.dat
connected to: 127.0.0.1
exported 2 records
[root@localhost bin]# cat user.dat
{ "_id" : { "$oid" : "4f81a4a1779282ca68fd8a5a" }, "uid" : 2, "username" : "Jerry", "age" : 100 }
{ "_id" : { "$oid" : "4f844d1847d25a9ce5f120c4" }, "uid" : 1, "username" : "Tom", "age" : 25 }
[root@localhost bin]#
命令執行完后使用命令查看，會發現目錄下生成了一個students.dat的文件
參數說明
-d 指明使用的庫, 本例中為” my_mongodb”
-c 指明要導出的表, 本例中為”user”
-o 指明要導出的文件名, 本例中為”user.dat”
從上面可以看到導出的方式使用的是JSON 的樣式
2、將foo庫中的表t1導出成json格式
[root@localhost bin]# ./mongoexport -d foo -c t1 -o /data/t1.json
connected to: 127.0.0.1
exported 1 records
[root@localhost bin]#
導出成功后我們看一下/data/t1.json文件的樣式
root@localhost data]# more t1.json
{ "_id" : { "$oid" : "4f927e2385b7a6814a0540a0" }, "age" : 2 }
[root@localhost data]#
3、導出為CSV格式的數據
[root@localhost bin]# ./mongoexport -d foo -c t2 --csv -f age,name -o /data/t2.csv
connected to: 127.0.0.1
exported 1 records
[root@localhost bin]#
查看/data/t2.csv的導出結果
[root@localhost data]# more t2.csv
age,name
1,"wwl"
[root@localhost data]#
三、Mongodb導入工具mongoexport
Mongodb中的mongoimport工具可以把一個特定格式文件中的內容導入到指定的collection中。該工具可以導入JSON格式數據，也可以導入CSV格式數據。
具體使用如下
- [root@localhost mongodb]# ./bin/mongoimport --help
- options:
- --help produce help message
- -v [ --verbose ] be more verbose (include multiple times for more
- verbosity e.g. -vvvvv)
- --version print the program's version and exit
- -h [ --host ] arg mongo host to connect to ( <set name>/s1,s2 for sets)
- --port arg server port. Can also use --host hostname:port
- --ipv6 enable IPv6 support (disabled by default)
- -u [ --username ] arg username
- -p [ --password ] arg password
- --dbpath arg directly access mongod database files in the given
- path, instead of connecting to a mongod server -
- needs to lock the data directory, so cannot be used
- if a mongod is currently accessing the same path
- --directoryperdb if dbpath specified, each db is in a separate
- directory
- --journal enable journaling
- -d [ --db ] arg database to use
- -c [ --collection ] arg collection to use (some commands)
- -f [ --fields ] arg comma separated list of field names e.g. -f name,age
- --fieldFile arg file with fields names - 1 per line
- --ignoreBlanks if given, empty fields in csv and tsv will be ignored
- --type arg type of file to import. default: json (json,csv,tsv)
- --file arg file to import from; if not specified stdin is used
- --drop drop collection first
- --headerline CSV,TSV only - use first line as headers
- --upsert insert or update objects that already exist
- --upsertFields arg comma-separated fields for the query part of the
- upsert. You should make sure this is indexed
- --stopOnError stop importing at first error rather than continuing
- --jsonArray load a json array, not one item per line. Currently
- limited to 4MB.
參數說明
-h:指明數據庫宿主機的IP
-u:指明數據庫的用戶名
-p:指明數據庫的密碼
-d:指明數據庫的名字
-c:指明collection的名字
-f:指明要導入那些列
四、常用數據導入實例
1、導入JSON 數據
[root@localhost mongodb]# ./bin/mongoimport -d test -c students students.dat
connected to: 127.0.0.1
imported 9 objects
[root@localhost mongodb]#
參數說明
-d:指明數據庫名，本例中為test
-c:指明collection名，本例中為students
students.dat：導入的文件名
2、導入CSV格式文件中的內容
[root@localhost mongodb]# ./bin/mongoimport -d test -c students --type csv --headerline --file students_csv.dat
connected to: 127.0.0.1
imported 10 objects
[root@localhost mongodb]#
參數說明：
-type:指明要導入的文件格式
-headerline:指明第一行是列名，不需要導入
-file：指明要導入的文件
以上所述就是本文的全部內容了，希望大家能夠喜歡。
