接口 IndexOptions

Builds the index in the background so that building an index an does not block other database activities. This option is only supported for mongodb database.

Create the index using the CONCURRENTLY modifier Works only in postgres.

Specifies a time to live, in seconds. This option is only supported for mongodb database.

The FULLTEXT modifier indexes the entire column and does not allow prefixing. Works only in MySQL.

NULL_FILTERED indexes are particularly useful for indexing sparse columns, where most rows contain a NULL value. In these cases, the NULL_FILTERED index can be considerably smaller and more efficient to maintain than a normal index that includes NULL values.

Works only in Spanner.

Fulltext parser. Works only in MySQL.

If true, the index only references documents with the specified field. These indexes use less space but behave differently in some situations (particularly sorts). This option is only supported for mongodb database.

The SPATIAL modifier indexes the entire column and does not allow indexed columns to contain NULL values. Works only in MySQL and PostgreSQL.

Indicates if this composite index must be unique or not.

Index filter condition.