The Indexes API enables you to create indexes for data collections, to make querying data faster.
An index is a map of a collection's data, organized according to fields that you select. An index increases the speed of queries by providing a query with a shortcut to the information it is looking for. Instead of iterating through every data item in the collection, a query can use the index to skip to potentially relevant items. The larger a collection is, the more time this saves.
With the Indexes API, your app can:
- Create regular indexes to accelerate query speed.
- Create unique indexes to enforce unique values.
- Access and drop existing indexes.
To learn about the differences between regular and unique indexes, see Index Types.
It's important to note the following points before starting to code:
- A collection can have up to 3 regular indexes (for up to 3 fields per index). It may also have 1 unique index (for 1 field).
- The value contained in an indexed field can't be larger than 982 bytes, including the collection name. For example, in a collection named "Products", the maximum length of each value in the indexed fields is 974 bytes.
- When an index creation fails, the failed index still occupies a slot. To remove the failed index and free up the slot for a new index, use the
dropIndex() function.
- Case-insensitive filters, such as
$startsWith, aren't accelerated by an index.
- Regular index: An index that increases query speed. Up to 3 fields can be selected for a regular index.
- Unique index: An index that increases query speed and enforces unique values for 1 field.