Identify the missing word(s) in the following sentence within the context of Microsoft Azure. One of the value-added features in Azure Database for MySQL and PostgreSQL is an implementation of the [?] in each database. While a slightly different implementation of the feature than in Azure SQL, the Query Store offers insightful actionable performance information to the DBA such as the abilities to: Track query performance over time and quickly identify the longest running and most expensive queries in your databases. Capture wait statistics. Change the capture mode from all queries, to top queries, or no queries. Adjust the data retention period and frequency of wait stats sampling.