How to migrate hive derby metastore to postgres metastore

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votes

I have been using derby as hive metastore for quite some time. Is there a way to migrate the metastore to Postgresql.

I am using Apache Hive - 0.13

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hivemetastore

1 Answers

0
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The best approach I have found so far is as below:

**Export from existing database**
Use the derby tool 'ij' (assuming you are placed in the root installation folder for the pillar):
java -cp lib/derby-10.10.1.1.jar:lib/derbytools-10.10.1.1.jar:lib/derbyclient-10.10.1.1.jar org.apache.derby.tools.ij
Then run the following commands to extract the content of the somedb database:
CONNECT 'jdbc:derby:/path/to/somedb'
CALL SYSCS_UTIL.SYSCS_EXPORT_TABLE(null, 'TABLE1', 'table1', null, null, null);
This should create the file: 'table1'.

**Import the data to the PostgreSQL database**
Run the 'psql' application on the console/terminal.
Log onto somedb and ingest data (and fix the automated sequences)
\c somedb
COPY table1 FROM '/path/to/table1' with csv;
SELECT SETVAL('table1_guid_seq', (SELECT MAX(guid) FROM table1));

Repeat this for all tables you want to export from derby and import into postgresql.