-`--output-path`, `-o`: The output directory of the tool. CSV files for the Druid segments, rules, config, datasource, and supervisors tables will be written to this directory.
-`--use-hex-blobs`, `-x`: If set, export BLOB payload columns as hexadecimal strings. This needs to be set if importing back into Derby. Default is false.
-`--booleans-as-strings`, `-t`: If set, write boolean values as "true" or "false" instead of "1" and "0". This needs to be set if importing back into Derby. Default is false.
When copying the local deep storage segments to S3, the rewrite performed by this tool requires that the directory structure of the segments be unchanged.
For example, if the cluster had the following local deep storage configuration:
```
druid.storage.type=local
druid.storage.storageDirectory=/druid/segments
```
If the target S3 bucket was `migration`, with a base key of `example`, the contents of `s3://migration/example/` must be identical to that of `/druid/segments` on the old local filesystem.
#### Migration to HDFS Deep Storage
By setting the options below, the tool will rewrite the segment load specs to point to a new HDFS deep storage location.
This helps users migrate segments stored in local deep storage to HDFS.
`--hadoopStorageDirectory`, `-h`: The HDFS path that will hold the migrated segments
When copying the local deep storage segments to HDFS, the rewrite performed by this tool requires that the directory structure of the segments be unchanged, with the exception of directory names containing colons (`:`).
For example, if the cluster had the following local deep storage configuration:
```
druid.storage.type=local
druid.storage.storageDirectory=/druid/segments
```
If the target hadoopStorageDirectory was `/migration/example`, the contents of `hdfs:///migration/example/` must be identical to that of `/druid/segments` on the old local filesystem.
Additionally, the segments paths in local deep storage contain colons(`:`) in their names, e.g.:
HDFS cannot store files containing colons, and this tool expects the colons to be replaced with underscores (`_`) in HDFS.
In this example, the `wikipedia` segment above under `/druid/segments` in local deep storage would need to be migrated to HDFS under `hdfs:///migration/example/` with the following path:
By setting the options below, the tool will rewrite the segment load specs to point to a new local deep storage location.
This helps users migrate segments stored in local deep storage to a new path (e.g., a new NFS mount).
`--newLocalPath`, `-n`: The new path on the local filesystem that will hold the migrated segments
When copying the local deep storage segments to a new path, the rewrite performed by this tool requires that the directory structure of the segments be unchanged.
For example, if the cluster had the following local deep storage configuration:
```
druid.storage.type=local
druid.storage.storageDirectory=/druid/segments
```
If the new path was `/migration/example`, the contents of `/migration/example/` must be identical to that of `/druid/segments` on the local filesystem.
## Running the tool
To use the tool, you can run the following from the root of the Druid package:
-`/tmp/csv` is the output directory. Please make sure that this directory exists.
## Importing Metadata
After running the tool, the output directory will contain `<table-name>_raw.csv` and `<table-name>.csv` files.
The `<table-name>_raw.csv` files are intermediate files used by the tool, containing the table data as exported by Derby without modification.
The `<table-name>.csv` files are used for import into another database such as MySQL and PostgreSQL and have any configured deep storage location rewrites applied.
Example import commands for Derby, MySQL, and PostgreSQL are shown below.
These example import commands expect `/tmp/csv` and its contents to be accessible from the server. For other options, such as importing from the client filesystem, please refer to the database's documentation.
LOAD DATA INFILE '/tmp/csv/druid_segments.csv' INTO TABLE druid_segments FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '\"' (id,dataSource,created_date,start,end,partitioned,version,used,payload); SHOW WARNINGS;
LOAD DATA INFILE '/tmp/csv/druid_rules.csv' INTO TABLE druid_rules FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '\"' (id,dataSource,version,payload); SHOW WARNINGS;
LOAD DATA INFILE '/tmp/csv/druid_config.csv' INTO TABLE druid_config FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '\"' (name,payload); SHOW WARNINGS;
LOAD DATA INFILE '/tmp/csv/druid_dataSource.csv' INTO TABLE druid_dataSource FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '\"' (dataSource,created_date,commit_metadata_payload,commit_metadata_sha1); SHOW WARNINGS;
LOAD DATA INFILE '/tmp/csv/druid_supervisors.csv' INTO TABLE druid_supervisors FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '\"' (id,spec_id,created_date,payload); SHOW WARNINGS;
```
### PostgreSQL
```sql
COPY druid_segments(id,dataSource,created_date,start,"end",partitioned,version,used,payload) FROM '/tmp/csv/druid_segments.csv' DELIMITER ',' CSV;
COPY druid_rules(id,dataSource,version,payload) FROM '/tmp/csv/druid_rules.csv' DELIMITER ',' CSV;
COPY druid_config(name,payload) FROM '/tmp/csv/druid_config.csv' DELIMITER ',' CSV;
COPY druid_dataSource(dataSource,created_date,commit_metadata_payload,commit_metadata_sha1) FROM '/tmp/csv/druid_dataSource.csv' DELIMITER ',' CSV;
COPY druid_supervisors(id,spec_id,created_date,payload) FROM '/tmp/csv/druid_supervisors.csv' DELIMITER ',' CSV;
