1. Prepare the configuration file (in JSON format) with the identified Source and Sink details. See Source Configuration Templates and Sink Configuration Templates .

   Here, you specify the file containing the DDL statement of the sink table in the schemaPath parameter of the source configuration template. Correspondingly, set the useSourceSchema configuration parameter to true in the sink configuration template.

   You can generate a custom schema as follows:

   • Note the names and data types for each column from the MongoDB-formatted JSON data. Use this information to create a schema DDL file for the Oracle NoSQL Database table.
   • In the schema file, name the first column (primary key) as id of type STRING. Include the same name and type for the remaining columns as recorded in the MongoDB-formatted JSON file.
   • Save the schema file and note down it's complete path.
   The following user-defined schema is used in this example:

   CREATE TABLE IF NOT EXISTS sampleMongoDBImp (id STRING, name STRING, scores JSON, PRIMARY KEY(SHARD(id)));

   You must include a renameFields transformation instructing NoSQL Database Migrator to convert the _id column to id while creating the table. For parameter details, see Transformation Configuration Templates. NoSQL Database Migrator creates a table with the custom schema at the sink.

   
   {
     "source" : {
       "type" : "file",
       "format" : "mongodb_json",
       "schemaInfo" : {
         "schemaPath" : "<complete/path/to/the/schema/file>"
       },
       "dataPath" : "<complete/path/to/the/MongoDB/Formatted/JSON/file>"
     },
     "sink" : {
       "type" : "nosqldb",
       "storeName" : "kvstore",
       "helperHosts" : ["phoenix126166:5000"],
       "table" : "sampleMongoDBImp",
       "includeTTL" : true,
       "schemaInfo" : {
         "useSourceSchema" : true
       },
       "overwrite" : false,
       "requestTimeoutMs" : 5000
     },
     "transforms": {
       "renameFields" : {
         "_id":"id"
       }
     },
     "abortOnError" : true,
     "migratorVersion" : "1.7.0"
   }

2. Open the command prompt and navigate to the directory where you extracted the NoSQL Database Migrator utility.

3. Run the runMigrator command by passing the configuration file. Use --config or -c option.

   $./runMigrator --config <complete/path/to/the/JSON/config/file>
   

4. The utility proceeds with the data migration, as shown below.

   creating source from given configuration:
   source creation completed
   creating sink from given configuration:
   sink creation completed
   creating migrator pipeline
   [nosqldb sink] : start loading DDLs
   [nosqldb sink] : executing DDL: CREATE TABLE IF NOT EXISTS sampleMongoDBImp (id INTEGER, name STRING, scores JSON, PRIMARY KEY(SHARD(id)))
   [nosqldb sink] : completed loading DDLs
   migration started
   Start writing data to OnDB Sink
   executing for source:mongoDBSample
   [mongo file source] : start parsing MongoDB JSON records from file: mongoDBSample.json
   Writing data to OnDB Sink completed.
   migration completed.
   Records provided by source=5, Records written to sink=5, Records failed=0,Records skipped=0.
   Elapsed time: 0min 0sec 72ms
   Migration completed.

Verification

 java -jar lib/sql.jar -helper-hosts localhost:5000 -store kvstore

sql-> select * from sampleMongoDBImp;
{"id":0,"name":"Aimee Zank","scores":[{"score":1.463179736705023,"type":"exam"},{"score":11.78273309957772,"type":"quiz"},{"score":35.8740349954354,"type":"homework"}]}
{"id":2,"name":"Corliss Zuk","scores":[{"score":67.03077096065002,"type":"exam"},{"score":6.301851677835235,"type":"quiz"},{"score":66.28344683278382,"type":"homework"}]}
{"id":1,"name":"Aurelia Menendez","scores":[{"score":60.06045071030959,"type":"exam"},{"score":52.79790691903873,"type":"quiz"},{"score":71.76133439165544,"type":"homework"}]}
{"id":3,"name":"Bao Ziglar","scores":[{"score":71.64343899778332,"type":"exam"},{"score":24.80221293650313,"type":"quiz"},{"score":42.26147058804812,"type":"homework"}]}
{"id":4,"name":"Zachary Langlais","scores":[{"score":78.68385091304332,"type":"exam"},{"score":90.2963101368042,"type":"quiz"},{"score":34.41620148042529,"type":"homework"}]}

5 rows returned