mysql8.0 新特性

1. Window functions: MySQL 8.0 now supports window functions, which allows users to perform complex analytical queries with ease.

2. Common Table Expressions (CTEs): CTEs are temporary result sets that can be used within a single SQL statement. This feature makes it easier to write complex queries and improves code readability.

3. Recursive Common Table Expressions (RCTEs): RCTEs are a special type of CTE that allows users to write recursive queries. This feature is useful for queries that involve hierarchical data.

4. JSON enhancements: MySQL 8.0 includes several enhancements to its JSON support, including better performance and improved functionality.

5. Invisible indexes: This feature allows users to mark an index as "invisible," which means that it will not be used by the query optimizer. This can be useful for testing the impact of removing an index without actually removing it.

6. Instant ADD COLUMN: MySQL 8.0 includes a new feature that allows users to add a new column to a table without copying the entire table. This can be useful for large tables with many columns.

7. Roles: MySQL 8.0 introduces the concept of roles, which allows users to define sets of privileges that can be assigned to multiple users.

8. Improved performance: MySQL 8.0 includes several performance improvements, including better support for multi-threaded queries and faster data loading.

9. Improved security: MySQL 8.0 includes several security enhancements, including improved password management and support for encrypted connections.

10. Improved replication: MySQL 8.0 includes several improvements to its replication capabilities, including support for multiple replication channels and better conflict detection and resolution.