1. Migrate data from MongoDB to Oracle NoSQL Database Cloud Service
  2. Understand the Files Used During Migration and Sample Outputs

Understand the Files Used During Migration and Sample Outputs

Review the following example files and command outputs used during data migration.

About MongoDB Formatted JSON Files

You can generate MongoDB formatted JSON files from MongoDB to migrate your data. Here's an example MongoDB formatted JSON file: 

[opc@oci-compute ~]$ head -3 ~/zips_orig.json 
{ "_id" : "01001", "city" : "AGAWAM", "loc" : [ -72.622739, 42.070206 ], "pop" : 15338, "state" : "MA" }
{ "_id" : "01002", "city" : "CUSHMAN", "loc" : [ -72.51564999999999, 42.377017 ], "pop" : 36963, "state" : "MA" }
{ "_id" : "01005", "city" : "BARRE", "loc" : [ -72.10835400000001, 42.409698 ], "pop" : 4546, "state" : "MA" }
[opc@oci-compute nosql-migrator-1.5.0]$
[opc@oci-compute ~]$ cat zips.json | wc -l29353
[opc@oci-compute ~]$

Sample command to split MongoDB formatted JSON file

[opc@oci-compute nosql-migrator-1.5.0]$ cat /home/opc/.oci/config 
[DEFAULT]
user=user_OCID
fingerprint=user_fingerprint
tenancy=tenancy_OCID
region=region_ID
key_file=full_path_to_private_key_pem_file
[opc@oci-compute nosql-migrator-1.5.0]$

About Oracle NoSQL Database Cloud Service Data Definition Language Files

When migrating data using the Oracle NoSQL Database Cloud Service custom schema method, the new Oracle NoSQL Database Cloud Service table schema has to be defined similar to the schema of the source table by using a Data Definition Language (DDL). The attribute names and types for the new table should be the same as the attribute names and types on the source table.

Here's an example of an Oracle NoSQL Database Cloud Service sample schema data definition language file. 

[opc@oci-compute nosql-migrator-1.5.0]$ cat /home/opc/movies.ddl CREATE TABLE IF NOT EXISTS movies (title String,year Number,info JSON, PRIMARY KEY(SHARD(title),year))
[opc@oci-compute nosql-migrator-1.5.0]$

About OCI Identity Files

The OCI Identity File contains information about the user performing a migration to Oracle NoSQL Database Cloud Service. Here's a sample OCI Identity File: 

[opc@oci-compute nosql-migrator-1.5.0]$ cat /home/opc/.oci/config 
[DEFAULT]
user=user_OCID
fingerprint=user_fingerprint
tenancy=tenancy_OCID
region=region_ID
key_file=full_file_path_to_PEM_file
[opc@oci-compute nosql-migrator-1.5.0]$

About Default Schema Oracle NoSQL Database Migrations Output

Migrating to MongoDB generates an output file with the JSON schema of the configuration. Here's an example output from a default schema Oracle NoSQL Database Migration: 

[opc@oci-compute nosql-migrator-1.5.0]$ ./runMigrator --config ./migrator-config-mongodbjson-bucket.json --log-level debug
2023-02-15 17:42:46.955 [INFO] Configuration for migration:
{
 "source" : {
 "type" : "object_storage_oci",
 "format" : "mongodb_json",
 "endpoint" : "https://objectstorage.us-phoenix-1.oraclecloud.com",
 "namespace" : "namespace_name",
 "bucket" : "bucket_name",
 "prefix" : "zipssa",
 "credentials" : "/home/opc/.oci/config",
 "credentialsProfile" : "DEFAULT"
 },
 "sink" : {
 "type" : "nosqldb_cloud",
 "endpoint" : "https://nosql.us-phoenix-1.oci.oraclecloud.com",
 "table" : "zips",
 "schemaInfo" : {
 "defaultSchema" : true,
 "readUnits" : 50,
 "writeUnits" : 50,
 "storageSize" : 25
 },
 "compartment" : "compartment_name",
 "includeTTL" : false,
 "credentials" : "/home/opc/.oci/config",
 "credentialsProfile" : "DEFAULT",
 "writeUnitsPercent" : 90,
 "overwrite" : true,
 "requestTimeoutMs" : 5000
 },
 "abortOnError" : true,
 "migratorVersion" : "1.5.0"
}
2023-02-15 17:42:46.959 [INFO] creating source from given configuration:
2023-02-15 17:42:48.993 [INFO] source creation completed
2023-02-15 17:42:48.993 [INFO] creating sink from given configuration:
2023-02-15 17:42:49.871 [INFO] sink creation completed
2023-02-15 17:42:49.873 [INFO] creating migrator pipeline
2023-02-15 17:42:49.873 [INFO] migration started
2023-02-15 17:42:49.873 [INFO] [cloud sink] : start loading DDLs
2023-02-15 17:42:49.883 [INFO] [cloud sink] : executing DDL: CREATE TABLE IF NOT EXISTS zips (id STRING, document JSON, PRIMARY KEY(SHARD(id))),limits: [50, 50, 25]
2023-02-15 17:42:54.988 [INFO] [cloud sink] : completed loading DDLs
2023-02-15 17:42:55.081 [INFO] [cloud sink] : start loading records
2023-02-15 17:42:55.082 [DEBUG] [cloud sink] : tableLimits=[50, 50, 25]
2023-02-15 17:42:55.095 [INFO] [OCI OS source] : start parsing JSON records from object: zipssaa.json
2023-02-15 17:44:40.935 [INFO] Processed total of 5000 records
2023-02-15 17:46:32.044 [INFO] Processed total of 10000 records
2023-02-15 17:47:49.844 [INFO] [OCI OS source] : start parsing JSON records from object: zipssab.json
2023-02-15 17:48:23.154 [INFO] Processed total of 15000 records
2023-02-15 17:50:14.265 [INFO] Processed total of 20000 records
2023-02-15 17:52:05.377 [INFO] Processed total of 25000 records
2023-02-15 17:52:49.843 [INFO] [OCI OS source] : start parsing JSON records from object: zipssac.json
2023-02-15 17:53:42.149 [DEBUG] [cloud sink] : [Thread:18] wrote 7356 records
2023-02-15 17:53:42.154 [DEBUG] [cloud sink] : [Thread:17] wrote 7317 records
2023-02-15 17:53:42.176 [DEBUG] [cloud sink] : [Thread:16] wrote 7316 records
2023-02-15 17:53:42.199 [DEBUG] [cloud sink] : [Thread:19] wrote 7364 records
2023-02-15 17:53:42.207 [INFO] migration completed.
Records provided by source=29,353, Records written to sink=29,353, Records failed=0, Records skipped=0.
Elapsed time: 10min 52sec 326ms
Migration completed.
[opc@oci-compute nosql-migrator-1.5.0]$

About Custom Schema Oracle NoSQL Database Migration Output

Migrating to MongoDB generates an output file with the JSON schema of the configuration. Here's an example output from a custom schema Oracle NoSQL Database Migration with a sample transform where _id is changed to id: 

opc@oci-compute nosql-migrator-1.5.0]$ ./runMigrator --config ./migrator-config-mongodbjson-bucket-src-schema.json --log-level debug
2023-02-22 16:59:32.864 [INFO] Configuration for migration:
{
  "source": {
    "type": "object_storage_oci",
    "format": "mongodb_json",
    "endpoint": "https://objectstorage.oci_region_ID.oraclecloud.com",
    "namespace": "namespace",
    "bucket": "bucket_name",
    "prefix": "source_json_filename_or_prefix",
    "schemaInfo": {
      "schemaObject": "collection_name_ddl"
    },
    "credentials": "/home/opc/.oci/config",
    "credentialsProfile": "DEFAULT"
  },
  "sink": {
    "type": "nosqldb_cloud",
    "endpoint": "https://nosql.oci_region_ID.oci.oraclecloud.com",
    "table": "new_Oracle_NoSQL_Database_Cloud_Service_table_name",
    "schemaInfo": {
      "useSourceSchema": true,
      "readUnits": 50,
      "writeUnits": 50,
      "storageSize": 25
    },
    "compartment": "compartment_name",
    "includeTTL": false,
    "credentials": "/home/opc/.oci/config",
    "credentialsProfile": "DEFAULT",
    "writeUnitsPercent": 90,
    "overwrite": true,
    "requestTimeoutMs": 5000
  },
  "transforms": {
    "renameFields": {
      "_id": "id"
    }
  },
  "abortOnError": true,
  "migratorVersion": "1.5.0"
}
2023-02-22 16:59:32.878 [INFO] creating source from given configuration:
2023-02-22 16:59:36.226 [INFO] source creation completed
2023-02-22 16:59:36.228 [INFO] creating sink from given configuration:
2023-02-22 16:59:37.328 [INFO] sink creation completed
2023-02-22 16:59:37.330 [INFO] creating migrator pipeline
2023-02-22 16:59:37.330 [INFO] migration started
2023-02-22 16:59:37.469 [INFO] [cloud sink] : start loading DDLs
2023-02-22 16:59:37.480 [INFO] [cloud sink] : executing DDL: CREATE TABLE zips ( id string, city string, loc json, pop number, state string, PRIMARY KEY ( id ) ),limits: [50, 50, 25]
2023-02-22 16:59:42.673 [INFO] [cloud sink] : completed loading DDLs
2023-02-22 16:59:42.754 [INFO] [cloud sink] : start loading records
2023-02-22 16:59:42.754 [DEBUG] [cloud sink] : tableLimits=[50, 50, 25]
2023-02-22 16:59:42.756 [INFO] [OCI OS source] : start parsing JSON records from object: zipssaa.json
2023-02-22 17:01:28.592 [INFO] Processed total of 5000 records
2023-02-22 17:03:19.698 [INFO] Processed total of 10000 records
2023-02-22 17:04:37.499 [INFO] [OCI OS source] : start parsing JSON records from object: zipssab.json
2023-02-22 17:05:10.810 [INFO] Processed total of 15000 records
2023-02-22 17:07:01.920 [INFO] Processed total of 20000 records
2023-02-22 17:08:53.031 [INFO] Processed total of 25000 records
2023-02-22 17:09:37.499 [INFO] [OCI OS source] : start parsing JSON records from object: zipssac.json
2023-02-22 17:10:29.807 [DEBUG] [cloud sink] : [Thread:17] wrote 7341 records
2023-02-22 17:10:29.810 [DEBUG] [cloud sink] : [Thread:16] wrote 7326 records
2023-02-22 17:10:29.832 [DEBUG] [cloud sink] : [Thread:18] wrote 7368 records
2023-02-22 17:10:29.854 [DEBUG] [cloud sink] : [Thread:19] wrote 7318 records
2023-02-22 17:10:29.860 [INFO] migration completed.
Records provided by source=29,353, Records written to sink=29,353, Records failed=0, Records skipped=0.
Elapsed time: 10min 52sec 524ms
Migration completed.
[opc@oci-compute nosql-migrator-1.5.0]$