這是處理可變長度路徑查詢的更複雜查詢計畫的範例。為了清楚起見,此範例僅顯示explain輸出的一部分。 在subQuery1中,注入...graph_1子查詢的DFEPipelineScan(ID 0) 和DFEChunkLocalSubQuery(ID 1) 負責掃描具有YPO程式碼的節點。 在subQuery1中,注入...graph_2子查詢的DFEChunkLocalSubQuery(ID 2) 負責掃描具...
outputColumnNames: _col0 Statistics: Numrows:1Data size:8Basic stats: COMPLETEColumnstats:NONEFile Output Operator compressed:trueStatistics: Numrows:1Data size:8Basic stats: COMPLETEColumnstats:NONEtable: input format: org.apache.hadoop.mapred.SequenceFileInputFormat output format: org.apache.hadoop...
(0.13%), Output: 20 rows (2.95kB) Input avg.: 166.33 rows, Input std.dev.: 141.42% TableScan[awsdatacatalog:HiveTableHandle{schemaName=default, tableName=cloudfront_logs,\ analyzePartitionValues=Optional.empty}, grouped = false] => [[date, time, location, bytes, requestip, method, host...
type指的是访问类型,可以衡量sql的好坏。 The type column of EXPLAIN output describes how tables are joined 常见的type有system,const,eq_ref,ref,range,index,all。显示sql是从最好到最坏。 system The table has only one row (= system tabl...【...
-no_prompt = do not prompt for user input -o <outfile>; = name of output file -r <requester>; = id of explain requester -s <schema>; = Schema or qualifier of source of Explain request (SOURCE_SCHEMA) -t = terminal output desired ...
{ "StartCost": 0, "RunCost": 1.3591655, "TotalCost": 1.3591655, "Output": { "Records": 50001, "RecordSize": 29, "Sorted": false } }, "ChildOperators": [ { "NodeName": "hostname:11820", "GroupName": "group2", "Role": "data", "Collection": "sample.employee", "Query": ...
mysql explain 文章目录 也不想多写什么 https://dev.mysql.com/doc/refman/8.0/en/explain-output.html https://dev.mysql.com/doc/refman/5.7/en/explain-output.html 需要说明的是 extra 的 Using where,网上很多解释是此信息表明需要回表查询;但是在 字段a的索引上执行 select ......
第4步:对build input建立位图向量。 第5步:如果内存中没有空间了,则将分区写至磁盘上。 第6步:读取小表S的剩余部分,重复第三步,直至小表S全部读完。 第7步:将分区按大小排序,选取几个分区建立hash table(这里选取分区的原则是使选取的数量最多)。
Input–Output TablesReady-Made GarmentsStructural TransformationUnderstanding the interlinkages of firms and sectors in the production process and how that leads to higher value added and trade growth has attracted increasing interest.doi:10.13140/RG.2.2.32449.97125Valerie Mercer-Blackman...
| input format: org.apache.hadoop.mapred.TextInputFormat | | output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat | | serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe | | | | Stage: Stage-0 | | Fetch Operator | ...