Mongodb导出csv数据
关于mongodb的客户端，最开始我使用的工具是mongobooster，后来升级变成了nosqlbooster，都是可以直接选择字段进行导出的，步骤如下：

但是后来导出的时候提示要进行收费了，不过依然提供了导出的命令，直接在命令行窗口执行也是可以的，步骤类似如下：

不过后来

我加上一些查询条件的时候发现每次执行导出的数据都是空，类似于以下的输出：

java0904@weigongdeMacBook-Pro ~ % mongoexport -v --host localhost:3717 --username root --password root --authenticationDatabase admin -d "car" -c "vinParse_query" --out /Users/java0904/Downloads/vinParse_query.csv  --fields supplier.classname,params.vin,params.key,ip,addtime,timestamp --type csv --query "{\"addtime\":{\"$gt\":\"2020-01-01\",\"$lt\":\"2020-02-02\"}}" --limit 10000000000 --sort {"_id":1}
2020-09-29T14:45:31.255+0800	connected to: mongodb://localhost:3717/
2020-09-29T14:45:32.275+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:33.277+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:34.277+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:35.276+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:36.277+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:37.276+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:38.278+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:39.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:40.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:41.278+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:42.277+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:43.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:44.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:45.276+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:46.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:47.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:48.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:49.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:50.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:51.278+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:52.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:53.278+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:54.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:55.279+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:55.447+0800	[........................]  car.vinParse_query  0/10000000000  (0.0%)
2020-09-29T14:45:55.447+0800	exported 0 records

你说恼人不，试了很多办法，网上查了很多命令，都不行，最终我查看了一下：

java0904@weigongdeMacBook-Pro ~ % mongoexport --help
Usage:mongoexport <options>Export data from MongoDB in CSV or JSON format.See http://docs.mongodb.org/manual/reference/program/mongoexport/ for more information.general options:--help                                      print usage--version                                   print the tool version and exitverbosity options:-v, --verbose=<level>                           more detailed log output (include multiple times for more verbosity, e.g. -vvvvv, or specify a numeric value, e.g. --verbose=N)--quiet                                     hide all log outputconnection options:-h, --host=<hostname>                           mongodb host to connect to (setname/host1,host2 for replica sets)--port=<port>                               server port (can also use --host hostname:port)ssl options:--ssl                                       connect to a mongod or mongos that has ssl enabled--sslCAFile=<filename>                      the .pem file containing the root certificate chain from the certificate authority--sslPEMKeyFile=<filename>                  the .pem file containing the certificate and key--sslPEMKeyPassword=<password>              the password to decrypt the sslPEMKeyFile, if necessary--sslCRLFile=<filename>                     the .pem file containing the certificate revocation list--sslAllowInvalidCertificates               bypass the validation for server certificates--sslAllowInvalidHostnames                  bypass the validation for server name--sslFIPSMode                               use FIPS mode of the installed openssl libraryauthentication options:-u, --username=<username>                       username for authentication-p, --password=<password>                       password for authentication--authenticationDatabase=<database-name>    database that holds the user's credentials--authenticationMechanism=<mechanism>       authentication mechanism to usekerberos options:--gssapiServiceName=<service-name>          service name to use when authenticating using GSSAPI/Kerberos ('mongodb' by default)--gssapiHostName=<host-name>                hostname to use when authenticating using GSSAPI/Kerberos (remote server's address by default)namespace options:-d, --db=<database-name>                        database to use-c, --collection=<collection-name>              collection to useuri options:--uri=mongodb-uri                           mongodb uri connection stringoutput options:-f, --fields=<field>[,<field>]*                 comma separated list of field names (required for exporting CSV) e.g. -f "name,age"--fieldFile=<filename>                      file with field names - 1 per line--type=<type>                               the output format, either json or csv (defaults to 'json') (default: json)-o, --out=<filename>                            output file; if not specified, stdout is used--jsonArray                                 output to a JSON array rather than one object per line--pretty                                    output JSON formatted to be human-readable--noHeaderLine                              export CSV data without a list of field names at the first line--jsonFormat=<type>                         the extended JSON format to output, either canonical or relaxed (defaults to 'relaxed') (default: relaxed)querying options:-q, --query=<json>                              query filter, as a JSON string, e.g., '{x:{$gt:1}}'--queryFile=<filename>                      path to a file containing a query filter (JSON)-k, --slaveOk                                   allow secondary reads if available (default true) (default: false)--readPreference=<string>|<json>            specify either a preference mode (e.g. 'nearest') or a preference json object (e.g. '{mode: "nearest", tagSets: [{a: "b"}], maxStalenessSeconds: 123}')--forceTableScan                            force a table scan (do not use $snapshot)--skip=<count>                              number of documents to skip--limit=<count>                             limit the number of documents to export--sort=<json>                               sort order, as a JSON string, e.g. '{x:1}'--assertExists                              if specified, export fails if the collection does not exist (default: false)

最有用的是下面这行：

-q, --query=<json>                              query filter, as a JSON string, e.g., '{x:{$gt:1}}'

你看，他这里写的是用json，我上面写的也是json啊，那么好，我再按照文档的提示操作一下，把字段名addtime去掉双引号，$gt也去掉双引号，外面使用单引号，但是依旧执行不成功，最终，成功的是如下的命令：

java0904@weigongdeMacBook-Pro ~ % mongoexport -v --host localhost:3717 --username root --password root --authenticationDatabase admin -d "car" -c "vinParse_query" --out /Users/java0904/Downloads/vinParse_query_202005.csv  --fields supplier.classname,params.vin,params.key,ip,addtime,timestamp,content.code,content.message --type csv --query '{"addtime":{"$gt":"2020-05-01","$lt":"2020-06-01"}}'  --sort {"_id":1}
2020-09-29T15:37:41.967+0800	connected to: mongodb://localhost:3717/
2020-09-29T15:37:43.069+0800	car.vinParse_query  0
2020-09-29T15:37:59.070+0800	car.vinParse_query  0
2020-09-29T15:38:00.072+0800	car.vinParse_query  0
2020-09-29T15:38:01.072+0800	car.vinParse_query  0
2020-09-29T15:38:02.072+0800	car.vinParse_query  0
2020-09-29T15:38:03.069+0800	car.vinParse_query  0
2020-09-29T15:38:04.072+0800	car.vinParse_query  0
2020-09-29T15:38:23.069+0800	car.vinParse_query  0
2020-09-29T15:38:24.069+0800	car.vinParse_query  0
2020-09-29T15:38:25.072+0800	car.vinParse_query  0
2020-09-29T15:38:26.072+0800	car.vinParse_query  8000
2020-09-29T15:38:27.071+0800	car.vinParse_query  8000
2020-09-29T15:38:28.072+0800	car.vinParse_query  8000
2020-09-29T15:38:29.070+0800	car.vinParse_query  8000
2020-09-29T15:38:30.072+0800	car.vinParse_query  8000
2020-09-29T15:38:31.072+0800	car.vinParse_query  8000
2020-09-29T15:38:32.072+0800	car.vinParse_query  8000
2020-09-29T15:38:33.071+0800	car.vinParse_query  8000
```shell
特此记录，以后再也不需要依赖客户端导出了