database-indexes

问题 I am creating a new Neo4j database. I have a type of node called User and I would like an index on the properties of user Identifier and EmailAddress . How does one go setting up an index when the database is new? I have noticed in the neo4j.properties file there looks to be support for creating indexes. However when I set these as so # Autoindexing # Enable auto-indexing for nodes, default is false node_auto_indexing=true # The node property keys to be auto-indexed, if enabled node_keys

问题 Imagine a table with multiple columns, say, id, a, b, c, d, e . I usually select by id , however, there are multiple queries in the client app that uses various conditions over subsets of the columns. When MySQL executes a query on a single table with multiple WHERE conditions on multiple columns, can it really make use of indexes created on different columns? Or the only way to make it fast is to create multi-column indexes for all possible queries? 回答1: Yes, MySQL can use multiple index for

问题 Closed . This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed last year . Given that indexing is so important as your data set increases in size, can someone explain how indexing works at a database-agnostic level? For information on queries to index a field, check out How do I index a database column. 回答1: Why is it needed? When data is stored on disk