Load a Schema from a DRDL File

The schema generation tool mongodrdl outputs a schema file in Document Relational Definition Language (DRDL) format. Examine the generated schema's table structure and field types to verify that the generated schema supports your reporting requirements.

You can manually edit the schema definition files to perform the following actions:

• Add fields that mongodrdl didn't discover within the subset of documents that it sampled

• Remove fields

• Remove tables

• Rename tables, so long as the collection field remains the same

• Rename fields using the sqlname option

When you're done editing your .drdl file, you can follow the steps in one of the following options:

• Option 1. Upload the schema, give it a name, and start mongosqld, specifying both the schema's name, source, and mode, as in the following steps:

  1. Use mongodrdl to upload the schema to your MongoDB deployment, similar to the following example:

     mongodrdl upload --host <hostName> --schemaSource schemas --drdl ./movies.drdl

     The string representation of the ObjectId of the uploaded schema is returned:

     5d793f3f6a26a3ce66c304ea

  2. Name your schema, using the name-schema command, similar to the following example:

     mongodrdl name-schema --name movies --schemaSource schemas --schema 5d793f3f6a26a3ce66c304ea

  3. Start mongosqld with a named schema, using --schemaSource, --schemaMode, and --schemaName options, similar to the following example:

     mongosqld --schemaMode custom --schemaSource schemas --schemaName movies

• Option 2. Start mongosqld with the --schema option to specify the path to the .drdl schema file.