Collection methods
HCL OneDB™ supports a subset of the MongoDB collection methods.
The collection methods can be run on a JSON collection
or a relational table. The syntax for collection methods in the mongo shell
is
db.collection_name.collection_method(),
where db refers to the current database, and collection_name
is the name of the JSON collection or relational table, collection_method is
the MongoDB collection method. For
example, db.cartype.count() determines the number of documents that are
contained in the cartype collection.
| Collection method | JSON collections | Relational tables | Details |
|---|---|---|---|
| aggregate | Yes | Yes | |
| count | Yes | Yes | |
| createIndex | Yes | Yes | For more information, see Index creation. |
| dataSize | Yes | No | |
| distinct | Yes | Yes | |
| drop | Yes | Yes | |
| dropIndex | Yes | Yes | |
| dropIndexes | Yes | No | |
| ensureIndex | Yes | Yes | For more information, see Index creation. |
| find | Yes | Yes | |
| findAndModify | Yes | Yes | For relational tables, findAndModify is supported only for tables that have a primary key. This method is not support sharded data. |
| findOne | Yes | Yes | |
| getIndexes | Yes | No | |
| getShardDistribution | No | No | |
| getShardVersion | No | No | |
| getIndexStats | No | No | |
| group | No | No | |
| indexStats | No | No | |
| insert | Yes | Yes | |
| isCapped | Yes | Yes | This command returns false because capped collections are not supported in HCL OneDB. |
| mapReduce | No | No | |
| reIndex | No | No | |
| remove | Yes | Yes | The justOne option is not supported. This command deletes all documents that match the query criteria. |
| renameCollection | No | No | |
| save | Yes | No | |
| stats | Yes | No | |
| storageSize | Yes | No | |
| totalSize | Yes | No | |
| update | Yes | Yes | The multi option is supported for JSON collections if update.one.enable=true in the wire listener properties file. For relational
tables, the multi-parameter is ignored and all documents that meet the query criteria are
updated. If update.one.enable=false, all documents that match the query
criteria are updated. |
| validate | No | No |
For more information about the MongoDB features, see http://docs.mongodb.org/manual/reference/.