Syntax

기본 구문

Create Index

• create_index([(‘index_name’, order)])

  • Creates an index on this collection.

    my_collection.create_index([(‘address’, 1)])

Show Index

• index_information()

  • Get information on collections’s indexes.

    my_collection.index_information()

Drop Index

• drop_index ([(‘index_name’, order)])

  • Drops the specified index on this collection.

  • To drop all indexes on this collection, use drop_indexes().

    my_collection.drop_index([(‘address’, 1)])

Compound Index

• Create indexes on more than one field.

• my_collection.create_index([
  (‘name’, pymongo.DESCENDING),
  (‘address’, pymongo.ASCENDING)])

PyMongo에서 가독성을 위해 값을 제공하고 있다. 아래는 같은 뜻으로 이해하면 되겠다.

pymongo.ASCENDING = 1, pymongo.DESCENDING = -1

Indexing on Embedded Document

• Embedded document와 Array에 인덱스를 사용하기 위해서는 아래와 같은 구문으로 사용하면 된다. 개념은 똑같기 때문에 이해하는 것에는 무리없을 것으로 보인다.

• Indexes can be created on keys in embedded documents.

  collection.create_index([('parent.child', pymongo.ASCENDING)])

• To use the index to search for specific array elements efficiently.

  collection.create_index([('items.name', pymongo.DESCENDING)])

Indexing Option

Unique Indexes

• Unique indexes guarantee that each value will appear at most once in the index

  collection.create_index([('key_1', 1)], unique=True)

Sparse Indexes

• Sparse indexes only contain entries for documents that have the indexed field skipping documents without it

  collection.create_index([('key_2', 1)], sparse=True)

Unique & Sparse

• Unique indexes guarantee that each value will appear at most once in the index

  collection.create_index([(key_3', 1)], unique=True, sparse=True)

Hint

• To override MongoDB’s default index selection and query optimization process.

  collection.find().sort([('key_4', 1)]).hint([('key_4', 1)])