MySQL explains how it would process the statement, including information about how tables are joined and in which order. For information about using EXPLAIN to obtain execution plan information, see Section 8.8.
To use the information that the openCypher explain feature provides, you need to understand some details about how the DFE query engine works (DFE being the engine that Neptune uses to process openCypher queries). The DFE engine translates every query into a pipeline of operators. Starting fro...
SORT:Operators and steps used when queries have to sort or merge result sets. SortsortSort performs the sorting specified by the ORDER BY clause as well as other operations such as UNIONs and joins. Can operate from disk. MergemergeProduces final sorted results of a query based on intermediate...
It reduces the amount of back-and-forth requests for information by capturing a great deal of commonly useful data about the performance of a SQL statement.DiffStats 和ExplainFull 可以生成详细的报告,这些报告对于解决SQL 语句的性能问题非常有用。 安装很简单,1分钟搞定,因为是几个纯文本函数,所以 ...
Join method – The method (e.g., hash, sort-merge, etc.) used to join tables with each other. Join type – The type of join (e.g., outer, anti, semi, etc.). Join order – The order in which the tables are joined to each other. Partition pruning – Are...
execute your query from the SQL editor and then selectExecution Planwithin the query results tab. The execution plan defaults toVisual Explain, but it also includes aTabular Explainview that is similar to what you see when executingEXPLAINin the MySQL client. For information about how MySQL execu...
See Batched Key Access Joins, for information about the Batched Key Access algorithm. Using MRR (JSON property: message) Tables are read using the Multi-Range Read optimization strategy. See Section 10.2.1.11, “Multi-Range Read Optimization”. Using sort_union(...), Using union(...)...
Using sort_union(...), Using union(...), Usingintersect(...) (JSON property: message) Theseindicate how index scans are merged for the index_merge jointype. See Section 9.2.1.4, “Index MergeOptimization”. Using temporary (JSON property: using_temporary_table) ...
Provides additional information about how MAXPAGES is calculated in the case of a jump scan. A jump scan can be conceptualized as multiple contiguous scans separated by jumps. If the value is 'TRUE', then MAXPAGES is the number of pages that are expected to be accessed by each contiguous sca...
Information about the environment when the query was executed. This includes: Memory pool size Memory pool ID Date format Date separator Time format Time separator Decimal point Sort sequence table name Sort sequence library name Language ID Query INI table name Query INI library name Query time li...