3 results about "Temporal database" patented technology

A method for intelligent query plan cache size management can be implemented. During the execution of multiple input queries in a database management system, this method measures the actual compilation time for generating query execution plans for the multiple input queries. The database management system may have a query execution plan cache, the size of which can store at least some query execution plans. This method monitors the difference between the actual compilation time and the ideal compilation time for generating query execution plans for the multiple input queries. The ideal compilation time can be estimated by assuming no query execution plans are evicted from the query execution plan cache. The method can adjust the size of the query execution plan cache based on the monitored difference.

The application provides a desulfurization system automatic slurry supply method and system, and belongs to the technical field of desulfurization. The method comprises the following steps: fitting a mathematical calculation model based on a previously established time database; wherein the time database is established based on boiler desulfurization operation data; obtaining desulfurization slurry supply parameters by using the mathematical calculation model based on the time database; wherein the desulfurization slurry supply parameters comprise limestone slurry supply amount of an absorption tower, absorption tower pH prediction value and slurry supply adjusting door opening degree; precise automatic slurry supply of the absorption tower, accurate absorption tower slurry pH control and accurate absorption tower slurry pH prediction are realized through the mathematical calculation model, which can effectively solve the problem that automatic slurry supply of the absorption tower is generally difficult to realize, thereby realizing automatic slurry supply of the absorption tower, improving the automation degree of the desulfurization device and reducing the workload of the operation personnel. Based on the desulfurization slurry supply parameters, a slurry supply control scheme is generated and executed. Accurate absorption tower slurry pH prediction is realized, and the reliability of the desulfurization system operation is improved.

This invention relates to the field of data processing. To address the problem of low efficiency in relational queries after database sharding and table partitioning, it provides a fast query method for tree-like relationships in massive code data. The code association table pre-stores all ancestor-descendant relationships, and the reverse linked list pre-stores the complete path, eliminating the need for recursion or multiple joins during queries. The partition key ensures that all queries are executed within a single shard, resulting in single code queries ≤20ms, tree queries ≤2 times, and query times ≤50ms for database access, improving performance by tens of times compared to traditional recursive queries.